LOANS AND ALLOWANCE FOR LOAN LOSSES (Schedule of Loans by Risk Category) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	$ 2,501,369	$ 1,867,349
Commercial Construction and Multifamily Real Estate Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	2,353,294	1,681,136
Commercial Construction and Multifamily Real Estate Loans [Member] | Pass
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	2,351,304	1,679,257
Commercial Construction and Multifamily Real Estate Loans [Member] | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	371	1,879
Commercial Construction and Multifamily Real Estate Loans [Member] | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	1,619
Real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	1,972,956	1,378,867
Real estate | Commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	1,505,537	949,778
Real estate | Commercial | Pass
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	1,505,166	949,395
Real estate | Commercial | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	371	383
Real estate | Construction
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	37,986	42,540
Real estate | Construction | Pass
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	37,986	42,540
Real estate | Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	360,346	307,126
Real estate | Multifamily | Pass
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	360,346	307,126
Real estate | One to four family
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	69,087	79,423
Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	449,425	381,692
Commercial and industrial | Pass
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	447,806	380,196
Commercial and industrial | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross		1,496
Commercial and industrial | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	1,619
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans and Leases Receivable, Gross	$ 78,988	$ 106,790