SECURITIES (Schedule of Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Securities [Line Items]
Securities—trading, Amortized Cost	$ 28,663	$ 30,154
Securities—trading	23,466	24,568
Available-for-sale Securities, Amortized Cost	1,338,863	806,336
Available-for-sale Securities, Gross Unrealized Gains	5,922	2,752
Available-for-sale Securities, Gross Unrealized Losses	(5,728)	(8,171)
Securities—available-for-sale	1,339,057	800,917
Held-to-maturity Securities, Amortized Cost	264,752	267,873
Held-to-maturity Securities, Gross Unrealized Gains	5,138	4,482
Held-to-maturity Securities, Gross Unrealized Losses	1,227	1,827
Securities—held-to-maturity	268,663	270,528
U.S. Government and agency obligations [Member]
Schedule of Securities [Line Items]
Securities—trading, Amortized Cost	1,230	1,230
Securities—trading	1,305	1,326
Available-for-sale Securities, Amortized Cost	87,509	57,288
Available-for-sale Securities, Gross Unrealized Gains	379	146
Available-for-sale Securities, Gross Unrealized Losses	(303)	(456)
Securities—available-for-sale	87,585	56,978
Held-to-maturity Securities, Amortized Cost	1,035	1,065
Held-to-maturity Securities, Gross Unrealized Gains	24	0
Held-to-maturity Securities, Gross Unrealized Losses	0	18
Securities—held-to-maturity	1,059	1,047
Municipal bonds [Member]
Schedule of Securities [Line Items]
Securities—trading, Amortized Cost	330	331
Securities—trading	331	335
Available-for-sale Securities, Amortized Cost	113,794	110,487
Available-for-sale Securities, Gross Unrealized Gains	1,194	455
Available-for-sale Securities, Gross Unrealized Losses	(342)	(1,089)
Securities—available-for-sale	114,646	109,853
Held-to-maturity Securities, Amortized Cost	193,987	196,989
Held-to-maturity Securities, Gross Unrealized Gains	4,638	4,173
Held-to-maturity Securities, Gross Unrealized Losses	1,015	1,272
Securities—held-to-maturity	197,610	199,890
Corporate bonds [Member]
Schedule of Securities [Line Items]
Securities—trading, Amortized Cost	27,089	26,959
Securities—trading	21,675	21,143
Available-for-sale Securities, Amortized Cost	10,567	10,255
Available-for-sale Securities, Gross Unrealized Gains	79	77
Available-for-sale Securities, Gross Unrealized Losses	(44)	(49)
Securities—available-for-sale	10,602	10,283
Held-to-maturity Securities, Amortized Cost	4,265	3,876
Held-to-maturity Securities, Gross Unrealized Gains	0	0
Held-to-maturity Securities, Gross Unrealized Losses	0	0
Securities—held-to-maturity	4,265	3,876
Mortgage-backed or related securities [Member]
Schedule of Securities [Line Items]
Securities—trading, Amortized Cost		1,620
Securities—trading		1,641
Available-for-sale Securities, Amortized Cost	1,093,203	598,899
Available-for-sale Securities, Gross Unrealized Gains	4,103	2,064
Available-for-sale Securities, Gross Unrealized Losses	(4,874)	(6,251)
Securities—available-for-sale	1,092,432	594,712
Held-to-maturity Securities, Amortized Cost	65,465	65,943
Held-to-maturity Securities, Gross Unrealized Gains	476	309
Held-to-maturity Securities, Gross Unrealized Losses	212	537
Securities—held-to-maturity	65,729	65,715
Asset-backed Securities [Member]
Schedule of Securities [Line Items]
Available-for-sale Securities, Amortized Cost	28,104	29,319
Available-for-sale Securities, Gross Unrealized Gains	157	0
Available-for-sale Securities, Gross Unrealized Losses	(54)	(326)
Securities—available-for-sale	28,207	28,993
Equity Securities [Member]
Schedule of Securities [Line Items]
Securities—trading, Amortized Cost	14	14
Securities—trading	155	123
Available-for-sale Securities, Amortized Cost	5,686	88
Available-for-sale Securities, Gross Unrealized Gains	10	10
Available-for-sale Securities, Gross Unrealized Losses	(111)	0
Securities—available-for-sale	$ 5,585	$ 98

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

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