Loans Receivable and Allowance For Loan Losses - Allowance for Loan Losses by Loan Categories (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
ALLOWANCE FOR LOAN LOSSES
Beginning balance	$ 12,349	$ 10,756
Provision (recapture) for loan losses	2,880	1,540
Charge-offs	(2,628)	(940)
Recoveries	628	993
Net recoveries (charge-offs)	(2,000)	53
Loans individually evaluated for impairment	182	975
Loans collectively evaluated for impairment	13,047	11,374
Ending balance	13,229	12,349
LOANS RECEIVABLE
Loans individually evaluated for impairment	3,128	2,947
Loans collectively evaluated for impairment	1,348,765	1,323,291
Total loans receivable	1,351,893	1,326,238
REAL ESTATE LOANS.
ALLOWANCE FOR LOAN LOSSES
Beginning balance	5,761	4,770
Provision (recapture) for loan losses	439	953
Charge-offs	(5)	(4)
Recoveries	11	42
Net recoveries (charge-offs)	6	38
Loans individually evaluated for impairment	15	125
Loans collectively evaluated for impairment	6,191	5,636
Ending balance	6,206	5,761
LOANS RECEIVABLE
Loans individually evaluated for impairment	2,635	834
Loans collectively evaluated for impairment	821,405	845,489
Total loans receivable	824,040	846,323
CONSUMER LOANS.
ALLOWANCE FOR LOAN LOSSES
Beginning balance	3,351	2,814
Provision (recapture) for loan losses	838	526
Charge-offs	(1,040)	(936)
Recoveries	617	947
Net recoveries (charge-offs)	(423)	11
Loans individually evaluated for impairment	167	150
Loans collectively evaluated for impairment	3,599	3,201
Ending balance	3,766	3,351
LOANS RECEIVABLE
Loans individually evaluated for impairment	493	428
Loans collectively evaluated for impairment	325,717	275,045
Total loans receivable	326,210	275,473
COMMERCIAL BUSINESS LOANS.
ALLOWANCE FOR LOAN LOSSES
Beginning balance	3,191	2,014
Provision (recapture) for loan losses	1,646	1,173
Charge-offs	(1,583)
Recoveries		4
Net recoveries (charge-offs)	(1,583)	4
Loans individually evaluated for impairment		700
Loans collectively evaluated for impairment	3,254	2,491
Ending balance	3,254	3,191
LOANS RECEIVABLE
Loans individually evaluated for impairment		1,685
Loans collectively evaluated for impairment	201,643	202,757
Total loans receivable	201,643	204,442
Unallocated Financing Receivables [Member]
ALLOWANCE FOR LOAN LOSSES
Beginning balance	46	1,158
Provision (recapture) for loan losses	(43)	(1,112)
Loans collectively evaluated for impairment	3	46
Ending balance	$ 3	$ 46

Financing Receivable, Allowance for Credit Loses, Recovery (Write-downs), Net

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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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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