INVESTMENT SECURITIES - INVESTMENT CATEGORY (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Available for sale
Less than 12 months Fair Value	$ 1,475	$ 190,631
Less than 12 months Unrealized Losses	(25)	(2,213)
12 months or more Fair Value	254,869	19,879
12 months or more Unrealized Losses	(1,430)	(647)
Total Fair Value	256,344	210,510
Total Unrealized Losses	$ (1,455)	$ (2,860)
Number of securities held	181	179
Number of securities held in an unrealized loss position	45	45
Held to maturity
Less than 12 months Fair Value	$ 500	$ 13,821
Less than 12 months Unrealized Losses	(1)	(126)
12 months or more Fair Value	21,855	4,937
12 months or more Unrealized Losses	(122)	(63)
Total Fair Value	22,355	18,758
Total Unrealized Losses	(123)	(189)
U.S. Treasury securities and U.S. Government agencies
Available for sale
Less than 12 months Fair Value		138,002
Less than 12 months Unrealized Losses		(1,107)
12 months or more Fair Value	189,503
12 months or more Unrealized Losses	(812)
Total Fair Value	189,503	138,002
Total Unrealized Losses	(812)	(1,107)
Held to maturity
Less than 12 months Fair Value	500	506
Less than 12 months Unrealized Losses	(1)	(2)
Total Fair Value	500	506
Total Unrealized Losses	(1)	(2)
Mortgage backed securities - residential
Available for sale
Less than 12 months Fair Value		9,427
Less than 12 months Unrealized Losses		(122)
12 months or more Fair Value	25,977	4,211
12 months or more Unrealized Losses	(213)	(98)
Total Fair Value	25,977	13,638
Total Unrealized Losses	(213)	(220)
Collateralized mortgage obligations
Available for sale
Less than 12 months Fair Value		37,547
Less than 12 months Unrealized Losses		(690)
12 months or more Fair Value	35,936	15,668
12 months or more Unrealized Losses	(387)	(549)
Total Fair Value	35,936	53,215
Total Unrealized Losses	(387)	(1,239)
Held to maturity
Less than 12 months Fair Value		13,315
Less than 12 months Unrealized Losses		(124)
12 months or more Fair Value	6,825
12 months or more Unrealized Losses	(59)
Total Fair Value	6,825	13,315
Total Unrealized Losses	(59)	(124)
Community Reinvestment Act mutual fund
Available for sale
Less than 12 months Fair Value	1,475	2,455
Less than 12 months Unrealized Losses	(25)	(45)
Total Fair Value	1,475	2,455
Total Unrealized Losses	(25)	(45)
Corporate bonds
Held to maturity
12 months or more Fair Value	15,030	4,937
12 months or more Unrealized Losses	(63)	(63)
Total Fair Value	15,030	4,937
Total Unrealized Losses	(63)	(63)
Trust preferred security
Available for sale
Less than 12 months Fair Value		3,200
Less than 12 months Unrealized Losses		(249)
12 months or more Fair Value	3,453
12 months or more Unrealized Losses	(18)
Total Fair Value	3,453	3,200
Total Unrealized Losses	$ (18)	$ (249)