| **Employee Benefit Plans**            | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                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| **Employee Benefit Plans [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  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| Employee Benefit Plans                | Employee Benefit PlansPension PlanCOB maintains a defined benefit pension plan. In September 2006, the Board of Directors of COB approved a modified freeze to the pension plan. Effective December 31, 2006, no new employees were eligible to enter the plan. Participants who were at least age 40, had earned 10 years of vesting service as an employee of COB and remained an active employee as of December 31, 2006 qualified for a grandfathering provision. In November 2010, COB’s Board of Directors approved an additional amendment to the plan which ceased participant benefit accruals as of December 31, 2010. The retirement benefits of all other participants in the pension plan were frozen as of December 31, 2006.Benefits are based on the employee's compensation, years of service and age at retirement. COB's funding policy is to contribute annually to the plan an amount which is not less than the minimum amount required by the Employee Retirement Income Security Act of 1974 and not more than the maximum amount deductible for income tax purposes.The following table sets forth the plan’s change in benefit obligation, plan assets and the funded status of the pension plan, using a December 31 measurement date, and amounts recognized in the consolidated statements as of December 31: (dollars in thousands)      2014 2013Change in Benefit Obligation    Benefit obligation at beginning of year $13,965 $15,342Service cost — —Interest cost 711 646Net actuarial (gain) loss 1,399 (1,219)Benefits paid (906) (804)Benefit obligation at end of year $15,169 $13,965Change in Plan Assets    Fair value of plan assets at beginning of year $12,831 $12,370Actual return on plan assets 362 1,265Employer contributions 150 —Benefits paid (906) (804)Fair value of plan assets at December 31 $12,437 $12,831Funded Status at End of Year $(2,732) $(1,134)Amounts Recognized in the Consolidated Balance Sheets    Other Liabilities $(2,732) $(1,134)Amounts Recognized in Accumulated Other Comprehensive Income    Net actuarial loss $6,855 $5,223Net amount recognized $6,855 $5,223Weighted-Average Allocation of Plan Assets at End of Year    Equity securities 46% 65%Debt securities 54 35Cash and cash equivalents — —Fixed income funds — —Total 100% 100%Weighted-Average Plan Assumptions at End of Year    Discount rate 4.50% 5.10%Expected long-term rate of return on plan assets 8.00% 8.00%Rate of increase in compensation levels 5.50% 5.50%The expected long-term rate of return on plan assets considers the portfolio as a whole and not on the sum of the returns on individual asset categories.Components of net periodic pension cost (income) and other amounts recognized in other comprehensive income are as follows: (dollars in thousands) 2014 2013 2012Net Periodic Pension Cost (Income)      Service cost $— $— $—Interest cost 711 646 668Expected return on plan assets (987) (958) (804)Amortization of prior service cost — — —Amortization of net actuarial loss 392 562 524Total pension cost $116 $250 $388Other Changes in Plan Assets and Benefit Obligations      Recognized in Other Comprehensive Income:      Net actuarial loss (gain) $1,632 $(2,089) $22Amortization of prior service credit — — —Total recognized in other comprehensive loss (income) 1,632 (2,089) 22Total Recognized in Net Periodic Pension Cost and Other Comprehensive Loss $1,748 $(1,839) $410The estimated net loss and prior service cost that will be amortized from accumulated other comprehensive income/(loss) into net periodic pension cost over the next year are approximately $0.5 million and $0, respectively.COB’s investment policies and strategies for the pension plan use a target allocation for equity and for debt securities based on the funding status of the plan. The investment goals attempt to maximize returns while remaining within specific risk management policies. While the risk management policies permit investment in specific debt and equity securities, a significant percentage of total plan assets are maintained in mutual funds, approximately 99.6% at December 31, 2014, to assist in investment diversification. Generally the investments are readily marketable and can be sold to fund benefit payment obligations as they become payable.The following table provides the fair values of investments held in the pension plan by major asset category:December 31, 2014(dollars in thousands) FairValue Quoted Prices in Active Markets for Identical Assets(Level 1) Significant Other Observable Inputs(Level 2)Equity securities $5,668 $5,668 $—Debt securities 6,726 6,726 —Other 43 43 —Total fair value of pension assets $12,437 $12,437 $—December 31, 2013(dollars in thousands) FairValue Quoted Prices in Active Markets for Identical Assets(Level 1) Significant Other Observable Inputs(Level 2)Equity securities $8,321 $8,321 $—Debt securities 4,473 4,473 —Other 37 37 —Total fair value of pension assets $12,831 $12,831 $—The equity securities measured at fair value consist primarily of stock mutual funds (Level 1 inputs). Debt securities include corporate bonds, bond mutual funds, U.S. government and agency securities and obligations of state and political subdivisions (Level 1 inputs). Other investments consist of money market deposits (Level 1 inputs). For further information regarding levels of input used to measure fair value, refer to Note 20.In 2014, COB contributed $150 thousand to its pension plan. COB expects to contribute $100 thousand to its pension plan in 2015. However, the assets of the COB Employees Pension Plan are less in value than the present value of the accrued benefits (vested and unvested) of the participants in the Pension Plan on a termination and projected benefit obligation basis.The estimated benefit payments for each year ending December 31 from 2015 through 2019 are as follows: $870 thousand in 2015, $940 thousand in 2016, $940 thousand in 2017, $920 thousand in 2018 and $930 thousand in 2019. The estimated benefit payments to be paid in the aggregate for the five year period from 2020 through 2024 are $4.7 million. The estimated benefit payments are based on the same assumptions used to measure the benefit obligation at December 31, 2014 and include estimated future employee service.Supplemental Executive Retirement PlansCOB has maintained three noncontributory, nonqualified SERPs, covering certain executive employees. Annual benefits payable under the first of these SERPs are based on factors similar to those for the pension plan, with offsets related to amounts payable under the pension plan and social security benefits. SERP costs, which are actuarially determined using the projected unit credit method and recorded on an unfunded basis, are charged to current operations and credited to a liability account on the consolidated balance sheet. In 2010, the Board of Directors approved an amendment to the plan which stopped additional benefit accrual under the SERP after December 31, 2010. This action did not impact a participant's vested or accrued benefit in the plan. In September, 2012 the Board of Directors approved an amendment to terminate the Plan.  The amendment provides for lump sum cash distributions of participant benefits in accordance with Internal Revenue Code Section 409A.  These payments were made in 2013 and there are no further obligations under this SERP.In connection with the acquisition by COB of Carolina Fincorp, Inc. in 2000, CommunityOne assumed the obligations of Richmond Savings Bank, Inc., SSB under its Nonqualified Supplemental Retirement Plan.  There was one retired executive covered under this plan, who was entitled to a retirement benefit of $30,000 per year payable for 10 years.  Benefit payments began in 2012.  In September, 2012 the Board of Directors approved an amendment to terminate the Plan.  The amendment provided for a lump sum cash distribution of  the participant benefit in accordance with Internal Revenue Code Section 409A.  These payments were made during 2013 and there are no future obligations under this SERP.As a result of the acquisition of Integrity Financial Corporation in 2006, CommunityOne assumed the obligations of a nonqualifying deferred compensation plan for the former president of Integrity. Under the plan provisions, benefit payments began in 2006 and were expected to be payable for 10 years; however, upon this former executive's death in 2014, the remaining balance will be paid during 2015, after which there will be no further obligations under this SERP. During 2014, 2013 and 2012, provisions of $11,000, $17,000, and $39,000 respectively, were expensed for future benefits to be provided under this plan. The total liability under this plan was $18,000 at December 31, 2014 and $0.3 million at December 31, 2013, respectively, and is included in other liabilities in the accompanying consolidated balance sheets. Payments amounting to $71,000 in 2014, $78,000 in 2013 and $80,000 in 2012 were made under the provisions of this SERP.The following table sets forth the change in benefit obligation, plan assets and the funded status of the three SERPs, using a December 31 measurement date, and amounts recognized in the consolidated statements as of December 31: (dollars in thousands)      2014 2013Change in Benefit Obligation    Benefit obligation at beginning of year $263 $1,345Service cost — —Interest cost 11 84Amendments to plan — —Net actuarial gain (185) (13)Benefits paid (71) (1,153)Benefit obligation at end of year $18 $263Change in Plan Assets    Employer contributions $71 $1,153Benefits paid (71) (1,153)Fair value of plan assets at end of year $— $—Funded Status at December 31 $(18) $(263)Amounts Recognized in the Consolidated Balance Sheets    Other Liabilities $18 $263Amounts Recognized in Accumulated Other Comprehensive Loss    Net actuarial gain $— $—Prior service cost — —Net amount recognized $— $—Weighted-Average Plan Assumption at End of Year:    Discount rate —% 7.00%Components of net periodic SERP cost and other amounts recognized in other comprehensive loss are as follows: (dollars in thousands) 2014 2013 2012Net Periodic SERP Cost      Service cost $— $— $—Interest cost 11 84 107Amortization of prior service cost — 155 31Amortization of net actuarial gain — (1,015) (48)Net periodic SERP cost (income) $11 $(776) $90Other Changes in Plan Assets and Benefit Obligations      Recognized in Other Comprehensive Income      Net actuarial loss (gain) $— $1,002 $(409)Amortization of prior service credit — (155) (31)Total recognized in other comprehensive loss (income) — 847 (440)Total Recognized in Net Periodic SERP (Income) Cost and Other Comprehensive Income (Loss) $11 $71 $(350)The estimated net (gain) loss and prior service cost that will be amortized from accumulated other comprehensive income (loss) into net periodic SERP cost over the next year are approximately $0 and $0 respectively.The remaining SERP is an unfunded plan. Consequently, there are no plan assets or cash contribution requirements other than for the direct payment of benefits.Other Postretirement Defined Benefit PlansCOB has maintained a postretirement benefit plan, which provides medical and life insurance benefits to retirees who obtained certain age and service requirements. The medical plan is contributory, with retiree contributions adjusted whenever medical insurance rates change. The life insurance plan is noncontributory.In conjunction with the modified freeze of the pension plan, the postretirement medical and life insurance plan was also amended. Effective December 31, 2006, no new employees are eligible to enter the postretirement medical and life insurance plan. Participants who were at least age 40, had earned 10 years of vesting service as an employee of COB and remained an active employee as of December 31, 2006 qualified for a grandfathering provision. In November 2010, COB’s Board of Directors approved an additional amendment to the plan which ceased participant benefit accruals as of December 31, 2010.The following table sets forth the plans change in benefit obligation, plan assets and the funded status of the postretirement plans, using a December 31 measurement date, and amounts recognized in the consolidated statements as of December 31: (dollars in thousands)      2014 2013Change in Benefit Obligation    Benefit obligation at beginning of year $1,138 $1,377Service cost — —Interest cost 55 57Net actuarial gain (15) (223)Plan participant contributions 82 81Benefits paid (175) (154)Benefit obligation at end of year $1,085 $1,138Change in Plan Assets    Employer contributions $93 $73Plan participant contributions 82 81Benefits paid (175) (154)Fair value of plan assets at end of year $— $—Funded Status at December 31 $(1,085) $(1,138)Amounts Recognized in the Consolidated Balance Sheets    Other Liabilities $1,085 $1,138Amounts Recognized in Accumulated Other Comprehensive Loss    Net actuarial loss $(147) $(138)Prior service credit (12) (16)Net amount recognized $(159) $(154)Weighted-Average Plan Assumption at End of Year:    Discount rate 4.50% 5.10%Increasing or decreasing the assumed medical cost trend rate by one percentage point would not have a significant effect on either the postretirement benefit obligation at December 31, 2014 or the aggregate of the service and interest cost components of net periodic postretirement benefit cost for the year ended December 31, 2014.Components of net postretirement benefit cost and other amounts recognized in other comprehensive income are as follows: (dollars in thousands) 2014 2013 2012Net Periodic Postretirement Benefit Cost      Service cost $— $— $—Interest cost 55 57 63Amortization of prior service credit (10) (4) (4)Amortization of net actuarial loss — — —Net periodic postretirement benefit cost $45 $53 $59Other Changes in Plan Assets and Benefit Obligations      Recognized in Other Comprehensive Income      Net actuarial gain $(15) $(223) $(84)Amortization of prior service cost 10 4 4Total recognized in other comprehensive (income) loss (5) (219) (80)Total Recognized in Net Periodic Postretirement Benefit Cost and Other Comprehensive (Income) Loss $40 $(166) $(21)The estimated net (gain) loss and prior service credit that will be amortized from accumulated other comprehensive income/(loss) into net periodic postretirement benefit cost over the next year are $(5,000) and $(4,000).The postretirement medical and life insurance plans are unfunded plans. Consequently, there are no plan assets or cash contribution requirements other than for the direct payment of benefits.The estimated benefit payments for each year ending December 31 from 2015 through 2019 are as follows: $60,000 in 2015, $60,000 in 2016, $70,000 in 2017, $70,000 in 2018 and $60,000 in 2019. The estimated benefit payments to be paid in the aggregate for the five year period from 2020 through 2024 are $350,000. The estimated benefit payments are based on the same assumptions used to measure the benefit obligation at December 31, 2014 and include estimated future employee service.Matching Retirement/Savings PlanCOB has a matching retirement/savings plan which permits eligible employees to make contributions to the plan up to a specified percentage of compensation as defined by the plan. A portion of the employee contributions are matched by COB based on the plan formula, which is $0.50 for each dollar on the first 6% of eligible pay deferred by the employee under the plan. Additionally, commencing in 2007, COB on a discretionary basis may make an annual contribution up to a specified percentage of compensation as defined by the plan to the account of each eligible employee. COB did not make a discretionary contribution in 2014, 2013 or 2012. The matching and discretionary contributions amounted to $0.6 million in 2014, $0.5 million in 2013, and $0.6 million in 2012.Granite sponsored a tax-qualified profit-sharing and savings retirement plan covering substantially all Granite employees. During July 2012, Granite's plan and COB's plan were merged together into an amended and restated CommunityOne 401(k) plan.  Contributions to the Granite plan were made at the discretion of the Board of Directors but were not permitted to exceed the maximum amount allowable for federal income tax purposes. There were no Company contributions made for the year ended December 31, 2012. The plan permitted eligible employees to make contributions to the plan up to a specified percentage of compensation as defined by the plan. Effective January 1, 2012, the plan was amended to provide a match on a portion of the employee contributions. The match was based on the plan formula, which is $0.50 for each dollar on the first 6% of eligible pay deferred by the employee under the plan. |

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| - Definition
The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.
+ References
No definition available.
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