SECURITIES (Summary of Amortized Costs and Estimated Fair Values of Available-For-Sale Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Investments [Line Items]
Available-for-sale, Amortized Cost	$ 742,634	$ 763,553
Available-for-sale, Unrealized Gains	7,204	7,434
Available-for-sale, Unrealized Losses	(7,482)	(7,924)
Available-for-sale, Fair Value	742,356	763,063
Held-to-maturity securities, at amortized cost	60,234	20,179
Held-to-maturity securities, Unrealized Gains	277	265
Held-to-maturity securities, Unrealized Losses	(702)	(19)
Held-to-maturity Securities, Fair Value	59,809	20,425
Obligations of U.S. government-sponsored enterprises
Schedule of Investments [Line Items]
Available-for-sale, Amortized Cost	4,967	4,962
Available-for-sale, Unrealized Gains	84	65
Available-for-sale, Unrealized Losses	0	0
Available-for-sale, Fair Value	5,051	5,027
Obligations of states and political subdivisions
Schedule of Investments [Line Items]
Available-for-sale, Amortized Cost	21,192	26,080
Available-for-sale, Unrealized Gains	481	697
Available-for-sale, Unrealized Losses	0	0
Available-for-sale, Fair Value	21,673	26,777
Held-to-maturity securities, at amortized cost	60,234	20,179
Held-to-maturity securities, Unrealized Gains	277	265
Held-to-maturity securities, Unrealized Losses	(702)	(19)
Held-to-maturity Securities, Fair Value	59,809	20,425
Mortgage-backed securities issued or guaranteed by U.S. government-sponsored enterprises
Schedule of Investments [Line Items]
Available-for-sale, Amortized Cost	381,403	377,657
Available-for-sale, Unrealized Gains	5,083	5,656
Available-for-sale, Unrealized Losses	(3,219)	(2,005)
Available-for-sale, Fair Value	383,267	381,308
Collateralized mortgage obligations issued or guaranteed by U.S. government-sponsored enterprises
Schedule of Investments [Line Items]
Available-for-sale, Amortized Cost	329,577	348,855
Available-for-sale, Unrealized Gains	1,483	953
Available-for-sale, Unrealized Losses	(4,187)	(5,911)
Available-for-sale, Fair Value	326,873	343,897
Private issue collateralized mortgage obligations
Schedule of Investments [Line Items]
Available-for-sale, Amortized Cost	5,495	5,999
Available-for-sale, Unrealized Gains	73	63
Available-for-sale, Unrealized Losses	(76)	(8)
Available-for-sale, Fair Value	$ 5,492	$ 6,054

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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