REGULATORY MATTERS, Reconciliation of Stockholders' Equity to Regulatory Capital for the Bank (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Stockholders' Equity to Regulatory Capital for the Bank [Line Items]
Stockholders' equity	$ 459,725us-gaap_StockholdersEquity	$ 435,506us-gaap_StockholdersEquity	$ 391,574us-gaap_StockholdersEquity
Non-allowable assets:
Accumulated other comprehensive loss	(8,547)	(4,759)	(9,640)
Total (Tier 2) risk-based capital	425,428us-gaap_Capital	397,935us-gaap_Capital
Minimum capital requirement	(406,910)us-gaap_TangibleCapital	(376,717)us-gaap_TangibleCapital
Tangible Capital [Member]
Reconciliation of Stockholders' Equity to Regulatory Capital for the Bank [Line Items]
Stockholders' equity	454,095	427,209
Non-allowable assets:
Mortgage Servicing Rights (MSR)	(35)	(63)
Accumulated other comprehensive loss	8,488	5,209
Goodwill	(55,638)	(55,638)
Tier I risk-based capital	406,910	376,717
General regulatory valuation allowance	0	0
Total (Tier 2) risk-based capital	406,910	376,717
Minimum capital requirement	176,998	158,298
Regulatory capital excess	229,912	218,419
Leverage Capital [Member]
Reconciliation of Stockholders' Equity to Regulatory Capital for the Bank [Line Items]
Stockholders' equity	454,095	427,209
Non-allowable assets:
Mortgage Servicing Rights (MSR)	(35)	(63)
Accumulated other comprehensive loss	8,488	5,209
Goodwill	(55,638)	(55,638)
Tier I risk-based capital	406,910	376,717
General regulatory valuation allowance	0	0
Total (Tier 2) risk-based capital	406,910	376,717
Minimum capital requirement	176,998	158,298
Regulatory capital excess	229,912	218,419
Total Risk-Based Capital [Member]
Reconciliation of Stockholders' Equity to Regulatory Capital for the Bank [Line Items]
Stockholders' equity	454,095	427,209
Non-allowable assets:
Mortgage Servicing Rights (MSR)	(35)	(63)
Accumulated other comprehensive loss	8,488	5,209
Goodwill	(55,638)	(55,638)
Tier I risk-based capital	406,910	376,717
General regulatory valuation allowance	18,518	21,218
Total (Tier 2) risk-based capital	425,428	397,935
Minimum capital requirement	263,988	238,338
Regulatory capital excess	$ 161,440	$ 159,597

General regulatory valuation allowance with respect to capital requirement.

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Capital requirement for mortgage servicing right.

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The amount of goodwill adjustment in determining regulatory capital.

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Adjusted reconciliation Tier 1 Risk Based Capital as defined in the regulations.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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The amount of total capital as defined in the regulations.

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The amount by which the company's Total Capital exceeds the minimum required for capital adequacy purposes.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Tangible capital as defined in the regulations (generally includes outstanding stock plus retained earnings) for banking institutions subject to Office of Thrift Supervision (OTS) capital requirements.

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