Parent Company Only Financial Statements Condensed Parent Company Only Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Net income	$ 10,687us-gaap_NetIncomeLoss	$ 24,465us-gaap_NetIncomeLoss	$ 2,713us-gaap_NetIncomeLoss
ESOP, stock options, and restricted stock compensation	384us-gaap_StockOptionPlanExpense	1,416us-gaap_StockOptionPlanExpense	1,987us-gaap_StockOptionPlanExpense
Change in deferred tax assets, net	5,602	(13,742)	(1,000)
Change in other assets	(690)	1,418	105
Changes in other liabilities	484	(685)	1,248
Net cash provided by operating activities	18,585	15,205	13,227
Net cash provided in investing activities	28,220	(2,611)	32,621
Proceeds from stock options exercises	3,611	3,023	0
Repurchase and retirement of common stock	(17,566)	(28,090)	0
Dividends paid	(2,938)us-gaap_PaymentsOfDividends	(1,895)us-gaap_PaymentsOfDividends	0us-gaap_PaymentsOfDividends
Net cash used by financing activities	1,669	(44,760)	(122,868)
Net increase (decrease) in cash	48,474	(32,166)	(77,020)
Cash and cash equivalents at beginning of year	55,575	87,741	164,761
Cash and cash equivalents at end of year	104,049	55,575	87,741
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	10,687	24,465	2,713
Equity in undistributed earnings of subsidiaries	(11,555)	(25,563)	(4,448)
Dividends received from subsidiary	72,300	14,491	0
ESOP, stock options, and restricted stock compensation	13	48	0
Change in deferred tax assets, net	(540)	(584)	0
Change in receivables from subsidiaries	8	(12)	0
Change in payables to subsidiaries	50	66	0
Change in other assets	(16)	119	(113)
Changes in other liabilities	(130)	(38)	260
Net cash provided by operating activities	70,817	12,992	(1,588)
Investments in subsidiaries	0	71	0
ESOP loan repayment	1,054	1,011	963
Net cash provided in investing activities	1,054	1,082	963
Proceeds from stock options exercises	3,611	3,023
Proceeds for vested awards	282	1,508	1,427
Repurchase and retirement of common stock	(17,566)	(28,090)	0
Dividends paid	(2,938)	(1,895)	0
Net cash used by financing activities	(16,611)	(25,454)	1,427
Net increase (decrease) in cash	55,260	(11,380)	802
Cash and cash equivalents at beginning of year	9,211	20,591	19,789
Cash and cash equivalents at end of year	$ 64,471	$ 9,211	$ 20,591

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

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The increase (decrease) during the reporting period in the obligations due for goods and services provided by the following types of related parties: a parent company and its subsidiaries, subsidiaries of a common parent, an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entities' management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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The increase (decrease) during the reporting period in the amount due to the reporting entity for good and services provided to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management, an entity and its principal owners, management, member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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The increase (decrease) during the reporting period in other current operating liabilities not separately disclosed in the statement of cash flows.

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The increase (decrease) during the reporting period in the value of prepaid expenses and other assets not separately disclosed in the statement of cash flows, for example, deferred expenses, intangible assets, or income taxes.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The cash outflow to reacquire common stock during the period.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow from the financed defined contribution plan to acquire shares of the entity. The plan initially holds the shares in a suspense account, which is collateral for the loan. As the plan makes payment on the debt, the shares are released from the suspense account and become available to be allocated to participant accounts.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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