INVESTMENT SECURITIES - AMORTIZED COST AND FV (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2008
Securities available for Sale - Amortized Cost
Due in one year or less	$ 85,073,000		$ 85,073,000
Due from one year to five years	156,828,000		156,828,000
Due from five years to ten years	10,000,000		10,000,000
Due beyond ten years	3,482,000		3,482,000
Total securities	456,133,000		456,133,000
Securities available for Sale - Fair Value
Due in one year or less	85,055,000		85,055,000
Due from one year to five years	156,225,000		156,225,000
Due from five years to ten years	10,240,000		10,240,000
Due beyond ten years	3,500,000		3,500,000
Total securities	458,719,000		458,719,000
Securities held to maturity - Carrying Value
Due from one year to five years	10,574,000		10,574,000
Due from five years to ten years	30,072,000		30,072,000
Total securities	65,177,000		65,177,000		$ 52,864,000
Securities held to maturity - Fair Value
Due from one year to five years	10,606,000		10,606,000
Due from five years to ten years	30,583,000		30,583,000
Total securities	$ 65,949,000		$ 65,949,000		$ 53,249,000
Number of Securities Held	185		185		179
Securities available for sale	$ 458,719,000		$ 458,719,000		$ 481,275,000
Total unrealized gain	(237,000)	$ (788,000)	892,000	$ 1,920,000
Private label mortgage backed security
Securities available for Sale - Amortized Cost
Securities not due at a single maturity date	3,245,000		3,245,000
Securities available for Sale - Fair Value
Securities not due at a single maturity date	$ 4,575,000		$ 4,575,000
Securities held to maturity - Fair Value
Number of Securities Held	1		1
Securities available for sale	$ 4,575,000		$ 4,575,000		4,777,000
Mortgage backed securities - residential
Securities available for Sale - Amortized Cost
Securities not due at a single maturity date	102,657,000		102,657,000
Securities available for Sale - Fair Value
Securities not due at a single maturity date	104,002,000		104,002,000
Securities held to maturity - Carrying Value
Securities not due at a single maturity date	153,000		153,000
Total securities	153,000		153,000		158,000
Securities held to maturity - Fair Value
Securities not due at a single maturity date	164,000		164,000
Total securities	164,000		164,000		170,000
Securities available for sale	104,002,000		104,002,000		73,004,000
Collateralized mortgage obligations
Securities available for Sale - Amortized Cost
Securities not due at a single maturity date	92,348,000		92,348,000
Securities available for Sale - Fair Value
Securities not due at a single maturity date	92,234,000		92,234,000
Securities held to maturity - Carrying Value
Securities not due at a single maturity date	24,378,000		24,378,000
Total securities	24,378,000		24,378,000		27,142,000
Securities held to maturity - Fair Value
Securities not due at a single maturity date	24,596,000		24,596,000
Total securities	24,596,000		24,596,000		27,268,000
Securities available for sale	92,234,000		92,234,000		87,654,000
Freddie Mac preferred stock
Securities available for Sale - Fair Value
Securities not due at a single maturity date	407,000		407,000
Securities held to maturity - Fair Value
Number of Securities Held						40,000
Other Than Temporary Impairment ("OTTI") charge						$ 2,100,000
Securities available for sale	407,000		407,000		483,000	$ 0
Total unrealized gain			407,000
Community Reinvestment Act mutual fund
Securities available for Sale - Amortized Cost
Securities not due at a single maturity date	2,500,000		2,500,000
Securities available for Sale - Fair Value
Securities not due at a single maturity date	2,481,000		2,481,000
Securities held to maturity - Fair Value
Securities available for sale	2,481,000		2,481,000		2,455,000
Corporate bonds
Securities held to maturity - Carrying Value
Total securities	40,182,000		40,182,000		25,058,000
Securities held to maturity - Fair Value
Total securities	40,723,000		40,723,000		25,307,000
Securities available for sale	$ 15,261,000		$ 15,261,000		$ 15,158,000
Percentage of concentration risk			11.00%		8.00%