MARKETABLE SECURITIES - Schedule of Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Available for sale:
Amortized Cost	$ 246,830	$ 160,182
Gross Unrealized Gains	832	16
Gross Unrealized Losses	1,429	3,273
Estimated Fair Value	246,233	156,925
Held to maturity:
Amortized Cost	182,248	189,371
Gross Unrealized Gains	3,409	1,484
Gross Unrealized Losses	1,130	4,700
Estimated Fair Value	184,527	186,155
Corporate bonds
Available for sale:
Amortized Cost	18,861	25,254
Gross Unrealized Gains	180	6
Gross Unrealized Losses	8	377
Estimated Fair Value	19,033	24,883
Municipal securities
Available for sale:
Amortized Cost	7,793	7,841
Gross Unrealized Gains	0	0
Gross Unrealized Losses	300	622
Estimated Fair Value	7,493	7,219
Mortgage-backed securities
Available for sale:
Amortized Cost	95,343	61,298
Gross Unrealized Gains	24	0
Gross Unrealized Losses	902	1,608
Estimated Fair Value	94,465	59,690
Collateralized mortgage obligations
Available for sale:
Amortized Cost	124,833	65,789
Gross Unrealized Gains	628	10
Gross Unrealized Losses	219	666
Estimated Fair Value	125,242	65,133
Municipal securities
Held to maturity:
Amortized Cost	148,021	149,420
Gross Unrealized Gains	2,869	901
Gross Unrealized Losses	530	3,889
Estimated Fair Value	150,360	146,432
Mortgage-backed securities
Held to maturity:
Amortized Cost	24,642	28,450
Gross Unrealized Gains	320	318
Gross Unrealized Losses	93	290
Estimated Fair Value	24,869	28,478
Collateralized mortgage obligations
Held to maturity:
Amortized Cost	9,585	11,501
Gross Unrealized Gains	220	265
Gross Unrealized Losses	507	521
Estimated Fair Value	$ 9,298	$ 11,245

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

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

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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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