The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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LOANS AND ALLOWANCE FOR LOAN LOSSES (Schedule of Loans by Impairment Method) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment, Allowance for loan losses	$ 418		$ 44
Collectively evaluated for impairment, Allowance for loan losses	24,026		18,898
Total ending allowance balance	24,444	$ 22,715	18,942	$ 18,493	$ 17,463	$ 14,887
Individually evaluated for impairment, Loans	5,380		1,550
Collectively evaluated for impairment, Loans	2,495,989		1,865,799
Total ending loan balance	2,501,369		1,867,349
Real estate
Loans and Leases Receivable Disclosure [Line Items]
Total ending loan balance	1,972,956		1,378,867
Real estate \| Commercial
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment, Allowance for loan losses	0		0
Collectively evaluated for impairment, Allowance for loan losses	14,229		9,037
Total ending allowance balance	14,229	13,006	9,037	8,551	8,139	7,136
Individually evaluated for impairment, Loans	371		383
Collectively evaluated for impairment, Loans	1,505,166		949,395
Total ending loan balance	1,505,537		949,778
Real estate \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment, Allowance for loan losses	0		0
Collectively evaluated for impairment, Allowance for loan losses	507		625
Total ending allowance balance	507	501	625	671	666	519
Individually evaluated for impairment, Loans	0		0
Collectively evaluated for impairment, Loans	37,986		42,540
Total ending loan balance	37,986		42,540
Real estate \| Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment, Allowance for loan losses	0		0
Collectively evaluated for impairment, Allowance for loan losses	2,353		2,047
Total ending allowance balance	2,353	2,249	2,047	1,700	1,557	1,156
Individually evaluated for impairment, Loans	0		0
Collectively evaluated for impairment, Loans	360,346		307,126
Total ending loan balance	360,346		307,126
Real estate \| One to four family
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment, Allowance for loan losses	60		0
Collectively evaluated for impairment, Allowance for loan losses	162		228
Total ending allowance balance	222	253	228	336	380	138
Individually evaluated for impairment, Loans	3,405		1,078
Collectively evaluated for impairment, Loans	65,682		78,345
Total ending loan balance	69,087		79,423
Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment, Allowance for loan losses	200		0
Collectively evaluated for impairment, Allowance for loan losses	6,290		6,257
Total ending allowance balance	6,490	6,142	6,257	6,326	6,053	5,578
Individually evaluated for impairment, Loans	1,047		0
Collectively evaluated for impairment, Loans	448,378		381,692
Total ending loan balance	449,425		381,692
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment, Allowance for loan losses	158		44
Collectively evaluated for impairment, Allowance for loan losses	485		704
Total ending allowance balance	643	$ 564	748	$ 909	$ 668	$ 360
Individually evaluated for impairment, Loans	557		89
Collectively evaluated for impairment, Loans	78,431		106,701
Total ending loan balance	$ 78,988		$ 106,790