| **Employee Benefit Plan**                             | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|-------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Compensation and Retirement Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Employee Benefit Plan                                 | Employee Benefit PlansThe Company previously sponsored a cash balance defined benefit pension plan that covered substantially all of its salaried employees (the “Pension Plan”). In November 2012, the Board of Directors approved the termination of the Pension Plan. The Pension Plan was frozen in March 2013 pending regulatory approvals, which were received in August 2014. As of December 31, 2014, the Pension Plan assets have been distributed to Pension Plan participants and $7.9 million was distributed to the Company’s 401(k) Plan to pay additional future benefits to current and future 401(k) plan participants over the next seven years. Subsequent to these distributions, the remaining Pension Plan assets of $23.8 million were reverted to the Company in December 2014.  During 2014, the Company recorded a total of $13.5 million in Pension charges on the Company’s Consolidated Statements of Income, which included $8.7 million for net periodic pension costs, including settlements related to the termination of the Pension Plan and $4.8 million of excise tax. In addition, the Company expects to record additional expenses of approximately $7.9 million as the assets in the Company’s 401(k) Plan are allocated to participants over the next seven years. See Deferred Compensation Plan section below for further information related to the Company’s 401(k) Plan. During 2012, the Company recognized a curtailment change of $2.1 million in the Company’s Consolidated Statements of Income as a result of the termination. During 2013 and 2012, the Company incurred settlement losses of $0.7 million and $1.2 million, respectively, related to cash distributions made to certain participants. Obligations and Funded StatusChange in projected benefit obligation and plan assets:  2014 2013Projected benefit obligation, beginning of year$23,531$26,741Service cost—225Interest cost625653Actuarial loss (gain)2,245(888)Benefits paid(95)(101)Settlements(26,306)(3,099)Projected benefit obligation, end of year$—$23,531    Fair value of assets, beginning of year$58,648$60,097Actual return on assets142,378Benefits and expenses paid(595)(728)Settlements(26,306)(3,099)Assets contributed to 401(k) Plan(7,940) —Assets reverted to the Company(23,821) —Fair value of assets, end of year$—$58,648    Funded status at end of year$— $35,117    Ratio of plan assets to projected benefit obligation—% 249%As a result of the Pension Plan termination, the Company had no prepaid pension asset or accumulated benefit obligation at December 31, 2014. At December 31, 2013, the Company has recorded a prepaid pension asset of $35.1 million and the accumulated benefit obligation of the Pension Plan was $23.5 million.A summary of the net periodic pension cost and other amounts recognized in other comprehensive income (loss) are as follows: 2014 2013 2012Service cost$— $225 $889Interest cost 625 653 712Expected return on assets550 (443) (2,315)Amortization of prior service costs— — 440Amortization of loss465 326 48Settlement charges7,107 739 1,162Curtailment charge— — 2,063Net periodic pension cost $8,747 $1,500 $2,999      Other changes in plan assets and obligations recognized in Other comprehensive income:     Prior service cost— — (2,503)(Gain) loss (5,392) (3,260)1,275Total other comprehensive income(5,392) (3,260) (1,228)Total net periodic pension cost and other comprehensive income (loss)$3,355 $(1,760)$1,771      As of December 31, 2014 there were no actuarial loss amounts not yet reflected in net periodic pension cost and included in Accumulated other comprehensive loss as they were recognized in net periodic cost during 2014 due to the final settlement of the Pension Plan in 2014. As of December 31, 2013, actuarial loss amounts not yet reflected in net periodic pension cost and included in accumulated other comprehensive loss were $5.4 million. Pension charges on the Statements of Income includes $4.8 million of excise tax. AssumptionsAssumptions used to develop end of period benefit obligations:  2014 2013Discount rateN/A 4.37%Rate of compensation increaseN/A N/AAssumptions used to develop net periodic pension cost:  2014 2013 2012Discount rate3.75% 4.37% 3.50%Expected long-term rate on plan assets—% —% 4.75%Rate of compensation increaseN/A N/A N/ATo develop the expected long-term rate of return on assets assumption, the Company considered the current level of expected returns on risk free investments (primarily government bonds), the historical level of the risk premium associated with the other asset classes in which the portfolio is invested and the expectations for future returns of each asset class. The expected return for each asset class was then weighted based on the target asset allocation to develop the expected long-term rate of return on assets assumption for the portfolio. This resulted in the selection of the 4.75% assumption in 2012. Early in 2014, the Pension Plan transferred the majority of its investments held in plan assets to U.S. Treasury securities to maintain the Pension Plan asset balance, which resulted in the selection of a minimal expected long-term rate on plan assets as the U.S. Treasury securities in 2014 and 2013. Plan AssetsDuring 2014, the Pension Plan transferred the majority of its investments held in plan assets to U.S. Treasury securities to maintain the Pension Plan asset balance. There were no Plan assets at December 31, 2014. At December 31, 2013, U.S. Treasury securities are fair valued based on quoted market prices in an active market. The following tables sets forth by level within the fair value hierarchy for Plan assets at December 31, 2013.  Assets at Fair Value as of December 31, 2013 Asset Category:Level 1 Level 2 Level 3 TotalCash$115 $— $—$115Money market funds697 — —697U.S. Treasuries57,836 — —57,836Total$58,648$—$—$58,648        The following table sets forth a summary of changes in the fair value of the Pension Plan’s level 3 assets for the year ended December 31, 2013.  There were no level 3 assets in the Pension Plan during 2014.  2013Balance, beginning of year$927Sales(1,648)Realized gain on sale721Unrealized gains relating to instruments still held at the reporting date—Balance, end of year$—  Deferred Compensation PlanThe Company maintains a 401(k) retirement plan covering substantially all officers and employees, which permits participants to defer up to the maximum allowable amount determined by the IRS of their eligible compensation. As part of the Pension Plan termination, the Company directed the Pension Plan to transfer $7.9 million of the Pension Plan’s surplus assets into a suspense account in the Company’s 401(k) Plan. The Company expects to use the $7.9 million, including any income earned on the assets held in the suspense account, for Company contributions under the Company’s 401(k) Plan over the next seven years.  The Company retains the risks and rewards of ownership of the assets held in the suspense account since they have not been allocated to participants as of December 31, 2014; therefore, the $7.9 million of unallocated assets held in the suspense account are recorded on the Company’s Consolidated Balance Sheets as Restricted investments as of December 31, 2014.  The Company will record expense for the fair value of the assets at the time the assets are allocated to participants. As of December 31, 2014, the assets held in the suspense account were invested in the Guaranteed Income Fund. The Guaranteed Income Fund is valued based upon the contributions made to the fund, plus earnings at guaranteed crediting rates, less withdrawals and fees, and is categorized as a level 2 financial instrument. The Company’s Retirement Plan Investment Committee will be responsible for investing decisions and allocation decisions of the suspense account. Refer to Note 8, Financial Instruments and Fair Value Measurements for further information on the three-tier fair value hierarchy. |

| X                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_CompensationAndRetirementDisclosureAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The entire disclosure for pension and other postretirement benefits.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2410-114920Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450702-114947Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414199&loc=d3e39622-114963Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39675-114964
+ Details**Name:**us-gaap_PensionAndOtherPostretirementBenefitsDisclosureTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |