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LOANS (Schedule of Loan Receivables) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 1,700,835		$ 1,420,966
Deferred fees	(1,906)		(1,070)
Loans, net of deferred fees and unamortized costs	1,698,929		1,419,896
Allowance for loan losses	(18,493)	$ (17,463)	(14,887)	$ (15,075)	$ (13,909)	$ (11,815)
Net loans	1,680,436		1,405,009
Real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	1,217,358		1,036,370
Real estate \| Commercial
Loans and Leases Receivable Disclosure [Line Items]
Total loans	893,077		783,745
Allowance for loan losses	(8,551)	(8,139)	(7,136)	(7,124)	(6,487)	(5,206)
Real estate \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Total loans	47,711		36,960
Allowance for loan losses	(671)	(666)	(519)	(524)	(557)	(409)
Real estate \| Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Total loans	253,775		190,097
Allowance for loan losses	(1,700)	(1,557)	(1,156)	(992)	(958)	(620)
Real estate \| One to four family
Loans and Leases Receivable Disclosure [Line Items]
Total loans	22,795		25,568
Allowance for loan losses	(336)	(380)	(138)	(87)	(85)	(109)
Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total loans	366,739		340,001
Allowance for loan losses	(6,326)	(6,053)	(5,578)	(6,003)	(5,560)	(5,364)
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	116,738		44,595
Allowance for loan losses	$ (909)	$ (668)	$ (360)	$ (345)	$ (262)	$ (107)