SECURITIES - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Available-for-sale:
Total Amortized Cost	$ 715,507	$ 275,734
Gross Unrealized Gains	431	566
Gross Unrealized Losses	(10,399)	(1,681)
Fair Value	705,539	274,619
Held-to-maturity:
Total Amortized Cost	13,275	35,505
Gross Unrealized Gains	61	142
Gross Unrealized Losses	(190)	(803)
Fair Value	13,146	34,844
SBA guaranteed securities
Available-for-sale:
Total Amortized Cost	104,111
Gross Unrealized Gains	129
Gross Unrealized Losses	(948)
Fair Value	103,292
Obligations of the U.S. Treasury and other U.S. government agencies or sponsored enterprises
Available-for-sale:
Total Amortized Cost		118,272
Gross Unrealized Gains		17
Gross Unrealized Losses		(403)
Fair Value		117,886
Mortgage-backed securities issued by U.S. government agencies or sponsored enterprises: residential
Available-for-sale:
Total Amortized Cost	250,580	99,876
Gross Unrealized Gains	297	452
Gross Unrealized Losses	(1,701)	(430)
Fair Value	249,176	99,898
Held-to-maturity:
Total Amortized Cost	10,841	14,358
Gross Unrealized Gains	61	140
Gross Unrealized Losses	(170)	(267)
Fair Value	10,732	14,231
Mortgage-backed securities issued by U.S. government agencies or sponsored enterprises: commercial
Available-for-sale:
Total Amortized Cost	65,986
Gross Unrealized Gains	0
Gross Unrealized Losses	(500)
Fair Value	65,486
Collateralized mortgage obligations issued by U.S. government agencies or sponsored enterprises: residential
Available-for-sale:
Total Amortized Cost	234,881	42,379
Gross Unrealized Gains	0	96
Gross Unrealized Losses	(6,434)	(563)
Fair Value	228,447	41,912
Held-to-maturity:
Total Amortized Cost	2,434	21,147
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(20)	(536)
Fair Value	2,414	20,613
Collateralized mortgage obligations issued by U.S. government agencies or sponsored enterprises: commercial
Available-for-sale:
Total Amortized Cost	36,151
Gross Unrealized Gains	0
Gross Unrealized Losses	(472)
Fair Value	35,679
Corporate debt securities
Available-for-sale:
Total Amortized Cost	5,789	3,788
Gross Unrealized Gains	5	1
Gross Unrealized Losses	0	(14)
Fair Value	5,794	3,775
Obligations of municipal subdivisions
Available-for-sale:
Total Amortized Cost	6,672	236
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(45)	(1)
Fair Value	6,627	235
CRA qualified investment fund
Available-for-sale:
Total Amortized Cost	11,337	11,183
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(299)	(270)
Fair Value	$ 11,038	$ 10,913

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

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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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