INVESTMENT SECURITIES - AMORTIZED COST AND FV (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Securities available for Sale - Amortized Cost
Due in one year or less	$ 80,069
Due from one year to five years	139,088
Due from five years to ten years	10,000
Due beyond ten years	3,503
Amortized Cost	419,911	$ 524,112
Securities available for Sale - Fair Value
Due in one year or less	79,732
Due from one year to five years	137,270
Due from five years to ten years	9,978
Due beyond ten years	3,900
Total securities	417,983	524,303
Securities held to maturity - Carrying Value
Due from one year to five years	10,441
Due from five years to ten years	30,191
Total securities	62,844	64,227
Securities held to maturity - Fair Value
Due from one year to five years	10,473
Due from five years to ten years	30,551
Total securities	63,515	65,133
Private label mortgage backed security
Securities available for Sale - Amortized Cost
Securities not due at a single maturity date	2,738
Amortized Cost	2,738	3,065
Securities available for Sale - Fair Value
Securities not due at a single maturity date	4,120
Total securities	4,120	4,449
Mortgage backed securities - residential
Securities available for Sale - Amortized Cost
Securities not due at a single maturity date	100,439
Amortized Cost	100,439	105,644
Securities available for Sale - Fair Value
Securities not due at a single maturity date	100,238
Total securities	100,238	106,374
Securities held to maturity - Carrying Value
Securities not due at a single maturity date	150
Total securities	150	151
Securities held to maturity - Fair Value
Securities not due at a single maturity date	160
Total securities	160	161
Collateralized mortgage obligations
Securities available for Sale - Amortized Cost
Securities not due at a single maturity date	84,074
Amortized Cost	84,074	87,867
Securities available for Sale - Fair Value
Securities not due at a single maturity date	82,745
Total securities	82,745	87,163
Securities held to maturity - Carrying Value
Securities not due at a single maturity date	22,062
Total securities	22,062	23,437
Securities held to maturity - Fair Value
Securities not due at a single maturity date	22,331
Total securities	22,331	23,656
Corporate bonds
Securities available for Sale - Amortized Cost
Amortized Cost	10,000	15,001
Securities available for Sale - Fair Value
Total securities	9,979	15,125
Securities held to maturity - Carrying Value
Total securities	40,168	40,175
Securities held to maturity - Fair Value
Total securities	$ 40,573	$ 40,858
Percentage of concentration risk	10.00%	9.00%