SECURITIES (Securities with Continuous Loss Position) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	$ 526,094	$ 518,373
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(4,038)	(7,283)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	118,568	68,099
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,690)	(888)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	644,662	586,472
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(5,728)	(8,171)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	59,119	108,094
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1,115	1,822
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	4,347	204
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(112)	(5)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	63,466	108,298
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	1,227	1,827
U.S. Government and agency obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	39,846	39,043
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(286)	(442)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	5,680	1,012
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(17)	(14)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	45,526	40,055
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(303)	(456)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value		1,047
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		18
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value		1,047
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss		18
Municipal bonds [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	32,559	60,765
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(169)	(1,087)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	13,023	556
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(173)	(2)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	45,582	61,321
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(342)	(1,089)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	40,230	64,802
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	903	1,267
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	4,347	204
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(112)	(5)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	44,577	65,006
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	1,015	1,272
Corporate bonds [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	300	5,206
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1)	(49)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	4,814	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(43)	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	5,114	5,206
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(44)	(49)
Mortgage-backed or related securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	437,934	403,431
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,417)	(5,604)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	95,051	47,467
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,457)	(647)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	532,985	450,898
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(4,874)	(6,251)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	18,889	42,245
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	212	537
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	18,889	42,245
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	212	537
Asset-backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	9,968	9,928
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(54)	(101)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	19,064
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	(225)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	9,968	28,992
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(54)	$ (326)
Equity Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	5,487
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(111)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	5,487
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ (111)