LOANS AND ALLOWANCE FOR LOAN LOSSES (Schedule of Loan Receivables) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Line Items]
Total loans	$ 2,105,284	$ 1,867,349
Deferred fees	(2,864)	(2,133)
Loans, net of deferred fees and unamortized costs	2,102,420	1,865,216
Allowance for loan losses	(20,834)	(18,942)	$ (16,260)	$ (14,887)
Net loans	2,081,586	1,846,274
Real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	1,586,887	1,378,867
Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total loans	421,503	381,692
Allowance for loan losses	(6,177)	(6,257)	(5,784)	(5,578)
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total loans	96,894	106,790
Allowance for loan losses	(706)	(748)	(580)	(360)
Commercial \| Real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	1,134,243	949,778
Allowance for loan losses	(10,885)	(9,037)	(7,800)	(7,136)
Construction \| Real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	46,245	42,540
Allowance for loan losses	(647)	(625)	(503)	(519)
Multifamily \| Real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	327,456	307,126
Allowance for loan losses	(2,111)	(2,047)	(1,210)	(1,156)
One to four family \| Real estate
Loans and Leases Receivable Disclosure [Line Items]
Total loans	78,943	79,423
Allowance for loan losses	$ (308)	$ (228)	$ (383)	$ (138)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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