FAIR VALUE OF FINANCIAL INSTRUMENTS (Fair Value By Balance Sheet Location) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets:
Securities—trading, Fair Value	$ 40,258us-gaap_TradingSecurities	$ 62,472us-gaap_TradingSecurities
Securities—available-for-sale	411,021us-gaap_AvailableForSaleSecurities	470,280us-gaap_AvailableForSaleSecurities
Securities—held-to-maturity	137,608	103,610
Liabilities:
Advances from FHLB at fair value	32,250	27,250
Carrying Value
Assets:
Cash and due from banks	126,072	137,349
Securities—trading, Fair Value	40,258	62,472
Securities—available-for-sale	411,021	470,280
Securities—held-to-maturity	131,258	102,513
Loans receivable held for sale	2,786	2,734
Loans receivable	3,831,034	3,415,711
FHLB stock	27,036	35,390
Bank-owned life insurance	63,759	61,945
Mortgage servicing rights	9,030	8,086
Liabilities:
Demand, interest-bearing checking, and money market	2,227,292	1,946,467
Regular savings	901,142	798,764
Certificates of deposit	770,516	872,695
Advances from FHLB at fair value	32,250	27,250
Junior subordinated debentures at fair value	78,001	73,928
Other borrowings	77,185	83,056
Estimated Fair Value
Assets:
Cash and due from banks	126,072	137,349
Securities—trading, Fair Value	40,258	62,472
Securities—available-for-sale	411,021	470,280
Securities—held-to-maturity	137,608	103,610
Loans receivable held for sale	2,807	2,751
Loans receivable	3,722,179	3,297,936
FHLB stock	27,036	35,390
Bank-owned life insurance	63,759	61,945
Mortgage servicing rights	12,987	11,529
Liabilities:
Demand, interest-bearing checking, and money market	1,998,649	1,697,095
Regular savings	784,006	695,863
Certificates of deposit	764,549	867,904
Advances from FHLB at fair value	32,250	27,250
Junior subordinated debentures at fair value	78,001	73,928
Other borrowings	77,185	83,056
Interest Rate Swap [Member] \| Carrying Value
Assets:
Derivatives	6,290	4,946
Liabilities:
Derivatives	6,290	4,946
Interest Rate Swap [Member] \| Estimated Fair Value
Assets:
Derivatives	6,290	4,946
Liabilities:
Derivatives	6,290	4,946
Interest Rate Contract [Member] \| Carrying Value
Assets:
Derivatives	317	130
Liabilities:
Derivatives	198	43
Interest Rate Contract [Member] \| Estimated Fair Value
Assets:
Derivatives	317	130
Liabilities:
Derivatives	$ 198	$ 43

Deposits, Certificates of Deposit, Fair Value Disclosure

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Deposits, Demand NOW and Money Market Accounts, Fair Value Disclosure

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Fair value portion 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.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investments in debt securities classified as held-to-maturity.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value portion of other liabilities.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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