|**Employee Retirement Benefits**                                   | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      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|**Compensation and Retirement Disclosure [Abstract]**              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Employee Retirement Benefits                                       | Employee Retirement BenefitsWe sponsor a qualified defined benefit pension plan. During 2008, we changed the form of retirement benefit we offer some associates to a company match on contributions to a 401(k) plan from the defined benefit pension plan. We closed entry into the pension plan for new associates as of June 30, 2008, and only participants40 yearsof age or older as of August 31, 2008, could elect to continue to participate. For participants remaining in the pension plan, we continue to contribute to fund future benefit obligations. Benefits for the defined benefit pension plan are based on years of credited service and compensation level. Contributions are based on the prescribed method defined in the Pension Protection Act. Our pension expense is based on certain actuarial assumptions and also is composed of several components that are determined using the projected unit credit actuarial cost method. The qualified plan has been amended to allow for distribution of vested balances to terminated participants.We also sponsor a defined contribution plan (401(k) plan). Matching company contributions totaled$11 million,$10 millionand$9 millionduring the years 2014, 2013 and 2012, respectively. Associates who are not accruing benefits under the pension plan are eligible to receive the company match of up to6 percentof cash compensation. We also pay all operating expenses for the 401(k) plan. Participants vest in the company match for the 401(k) plan afterthreeyears of eligible service.We maintain a supplemental executive retirement plan (SERP) with a benefit obligation of$13 millionatyear-end 2014 and$9 millionat year-end 2013, which is included in the projected benefit obligation. The company also makes available to a select group of associates the CFC Top Hat Savings Plan, a nonqualified deferred compensation plan, which had a fair value of$18 millionand$14 millionat December 31, 2014 and 2013, respectively.Defined Benefit Pension Plan AssumptionsWe evaluate our pension plan assumptions annually and update them as necessary. This is a summary of the weighted-average assumptions used to determine our benefit obligations at December 31 for the plans:Qualified Pension PlanSERP2014201320142013Discount rate4.25%5.15%4.05%4.80%Rate of compensation increase2.75-3.252.75-3.252.75-3.252.75-3.25To determine the discount rate for each plan, a theoretical settlement portfolio of high quality rated corporate bonds was chosen to provide payments approximately matching the plan’s projected benefit payments. A single interest rate for each plan was determined resulting in a discounted value of the plan's benefit payments that equates to the market value of the selected bonds. The discount rate is reflective of current market interest rate conditions and our plan's liability characteristics. Based on this analysis, we decreased the rate from the prior year by0.90percentage points for the qualified pension plan and by0.75percentage points for the SERP. Compensation increase assumptions reflect anticipated rates of inflation, real return on wage growth and merit and promotional increases. The mortality assumption was updated in 2014 to the RP-2014 Employee Mortality Tables and RP-2014 Annuitant Mortality Tables for males and females projected generationally with Scale MP-2014. The updated mortality table did not have a significant impact on our financial statements as our qualified plan assumes benefits will be paid in the form of lump sums.This is a summary of the weighted-average assumptions used to determine our net expense for the plans:Qualified Pension PlanSERP201420132012201420132012Discount rate5.15%4.20%5.10%4.80%3.95%4.75%Expected return on plan assets7.257.507.50n/an/an/aRate of compensation increase2.75-3.252.75-3.253.50-5.502.75-3.252.75-3.253.50-5.50The discount rate was increased by0.95percentage points for the qualified pension plan and0.85percentage points for the SERP due to market interest rate conditions in 2014. The discount rate assumptions for our benefit obligation generally track with high quality rated corporate bond yields chosen in our theoretical settlement portfolio, and yearly adjustments reflect any changes to those bond yields. We believe the expected return on plan assets is representative of the expected long-term rate of return on these assets, which is consistent with 2014 expectations of interest rates and based partially on the fact that the plan’s common stock holdings pay dividends. We believe this rate is representative of the expected long-term rate of return on these plan assets. We review historical actual return on plan assets when determining our expected long-term rate of return. Total portfolio return for 2014 was11.7percent and for 2013 was24.0percent. Our compensation increase assumptions in 2014 reflect anticipated rates of inflation, real return on wage growth and merit and promotional increases.Benefit obligation activity using an actuarial measurement date for our qualified plan and SERP at December 31 follows:(Dollars in millions)At December 31,20142013Change in projected benefit obligation:Benefit obligation, January 1$284$320Service cost1013Interest cost1513Actuarial loss (gain)35(34)Benefits paid(27)(28)Other2—Projected benefit obligation, December 31$319$284Accumulated benefit obligation$284$257Change in plan assets:Fair value of plan assets, January 1$280$238Actual return on plan assets3055Employer contribution515Benefits paid(27)(28)Fair value of plan assets, December 31$288$280Funded status, December 31$(31)$(4)The decreases in discount rate and lump sum rate resulted in an increase in actuarial loss and projected benefit obligation from 2013 and an increase in unfunded status.A reconciliation follows of the funded status for our qualified plan and SERP at the end of the measurement period to the amounts recognized in the consolidated balance sheets at December 31:(Dollars in millions)At December 31,20142013Pension amounts recognized in the consolidated balance sheets:Other assets$—$4Other liabilities(31)(8)Net amount recognized$(31)$(4)Amounts recognized in accumulated other comprehensive income:Net actuarial loss$34$18Prior service cost2—Total$36$18The change in the amount recognized in other comprehensive income is largely due to the decrease in discount rate and corresponding decreases in assumed lump sum rates.Below are the components of our net periodic benefit cost, as well as other changes in plan assets and benefit obligations recognized in other comprehensive income for our qualified plan and SERP at December 31:(Dollars in millions)Years ended December 31,201420132012Net periodic benefit cost:Service cost$10$13$12Interest cost151314Expected return on plan assets(17)(17)(16)Amortization of actuarial loss and prior service cost298Other32—Net periodic benefit cost$13$20$18(Dollars in millions)Years ended December 31,201420132012Other changes in plan assets and benefit obligations recognized inother comprehensive income:Current year actuarial loss (gain)$21$(72)$20Amortization of actuarial loss(5)(10)(6)Current year prior service cost2——Amortization of prior service cost—(1)(1)Total recognized in other comprehensive loss (income)$18$(83)$13The total recognized in net periodic benefit cost and other comprehensive income was a net cost of$31 million, net benefit of$63 million, and a net cost of$31 millionfor the years ended December 31, 2014, 2013 and 2012, respectively. The change in the amount recognized in other comprehensive income from 2013 is largely due to decreases in discount and lump sum rates, partially offset with greater than anticipated return on plan assets. The estimated costs to be amortized from AOCI into net periodic benefit cost over the next year for our plans are$5 millionin actuarial loss and$1 millionin prior service cost.Defined Benefit Pension Plan AssetsThe pension plan assets are managed to maximize total return over the long term while providing sufficient liquidity and current return to satisfy the cash flow requirements of the plan. The plan’s day-to-day investment decisions are managed by our internal investment department; however, overall investment strategies are discussed with our employee benefits committee. Our investment strategy, currently driven by the low interest rate environment, is to weight our portfolio towards large cap, high quality, dividend growing equities that we have historically favored. As our plan matures and interest rates normalize, we expect a greater allocation to fixed income securities to better align asset and liability market risks. Our fixed-maturity bond portfolio is investment grade. The plan does not engage in derivative transactions.Excluding cash, during 2014 we held approximately81 percentof our pension portfolio in domestic common equity investments, which reflect the long-term time horizon of pension obligations. The remainder of the portfolio consisted of12 percentin states, municipalities and taxable political subdivisions fixed-maturity investments and7 percentin domestic corporate fixed-maturity investments. Our common equity portfolio consisted of23 percentin the financial sector,19 percentin the information technology sector,14 percentin the healthcare sector and12 percentin the industrial sector at year-end 2014. No additional sectors accounted for10 percentor more of our common equity portfolio balance at year-end 2014. We had$11 millionof cash on hand at December 31, 2014, to cover retirements.Investments in securities are valued based on the fair value hierarchy outlined in Note 3, Fair Value Measurements. The pension plan did not have any liabilities carried at fair value during the years ended December 31, 2014 and 2013. There have been no transfers between Level 1 and Level 2 for the years ended December 31, 2014 and 2013. The following table shows the fair value hierarchy for those assets measured at fair value on a recurring basis at December 31, 2014 and 2013. Excluded from the table below is cash on hand of$11 millionand$19 millionat December 31, 2014 and 2013.(Dollars in millions)Quoted prices inactive markets foridentical assets (Level 1)Significant otherobservable inputs (Level 2)Significantunobservableinputs(Level 3)TotalAt December 31, 2014Fixed maturities, available for sale:States, municipalities and political subdivisions$—$33$—$33Corporate securities—19—19Total fixed maturities, available for sale—52—52Common equities, available for sale225——225Total$225$52$—$277At December 31, 2013Fixed maturities, available for sale:States, municipalities and political subdivisions$—$32$—$32Corporate securities—21—21Total fixed maturities, available for sale—53—53Common equities, available for sale208——208Total$208$53$—$261Our pension plan assets included467,113shares of the company’s common stock at both December 31, 2014 and 2013, which had a fair value of$24 millionat both December 31, 2014 and 2013. The defined benefit pension plan did not purchase any shares of our common stock during 2014 and 2013. No shares of our common stock were sold during 2014. During 2013, the pension plan sold100,000shares of the company’s common stock for a realized gain of$5 million. The company paid$1 millionin cash dividends on our common stock to the pension plan in both 2014 and 2013.We contributed$5 millionto our qualified plan during the first quarter of 2015 and expect to pay out$3 millionof benefit payments from the SERP during 2015. We expect to make the following benefit payments for our qualified plan and SERP, reflecting expected future service:(Dollars in millions)Years ended December 31,201520162017201820192020 - 2024Expected future benefit payments$26$32$29$23$24$142
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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      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|At December 31, 2014                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Fixed maturities, available for sale:                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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|Total fixed maturities, available for sale                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Common equities, available for sale                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Total                                                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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|At December 31, 2013                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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