MARKETABLE SECURITIES - Schedule of Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Available for sale:
Amortized Cost	$ 216,494	$ 160,182
Gross Unrealized Gains	324	16
Gross Unrealized Losses	2,355	3,273
Estimated Fair Value	214,463	156,925
Held to maturity:
Amortized Cost	185,837	189,371
Gross Unrealized Gains	1,989	1,484
Gross Unrealized Losses	3,414	4,700
Estimated Fair Value	184,412	186,155
Corporate bonds
Available for sale:
Amortized Cost	25,223	25,254
Gross Unrealized Gains	73	6
Gross Unrealized Losses	123	377
Estimated Fair Value	25,173	24,883
Municipal securities
Available for sale:
Amortized Cost	7,817	7,841
Gross Unrealized Gains	0	0
Gross Unrealized Losses	539	622
Estimated Fair Value	7,278	7,219
Mortgage-backed securities
Available for sale:
Amortized Cost	80,766	61,298
Gross Unrealized Gains	15	0
Gross Unrealized Losses	1,236	1,608
Estimated Fair Value	79,545	59,690
Collateralized mortgage obligations
Available for sale:
Amortized Cost	102,688	65,789
Gross Unrealized Gains	236	10
Gross Unrealized Losses	457	666
Estimated Fair Value	102,467	65,133
Municipal securities
Held to maturity:
Amortized Cost	148,520	149,420
Gross Unrealized Gains	1,428	901
Gross Unrealized Losses	2,621	3,889
Estimated Fair Value	147,327	146,432
Mortgage-backed securities
Held to maturity:
Amortized Cost	26,900	28,450
Gross Unrealized Gains	312	318
Gross Unrealized Losses	191	290
Estimated Fair Value	27,021	28,478
Collateralized mortgage obligations
Held to maturity:
Amortized Cost	10,417	11,501
Gross Unrealized Gains	249	265
Gross Unrealized Losses	602	521
Estimated Fair Value	$ 10,064	$ 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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