Loans Receivable Held for Investment, Activity in Allowance for Loan Losses by Loan Type (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	$ 3,215	$ 3,211	$ 3,215	$ 3,182
Provision for (recapture of) loan losses	81	0	81	29
Recoveries	0	4	0	4
Loans charged off	0	0	0	0
Ending balance	3,296	3,215	3,296	3,215
Real Estate [Member] \| Single Family [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	275	308	296	312
Provision for (recapture of) loan losses	(105)	0	(126)	(4)
Recoveries	0	4	0	4
Loans charged off	0	0	0	0
Ending balance	170	312	170	312
Real Estate [Member] \| Multi-Family [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	2,473	2,408	2,433	2,319
Provision for (recapture of) loan losses	133	16	173	105
Recoveries	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	2,606	2,424	2,606	2,424
Real Estate [Member] \| Commercial Real Estate [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	219	140	222	133
Provision for (recapture of) loan losses	8	29	5	36
Recoveries	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	227	169	227	169
Real Estate [Member] \| Church [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	221	323	237	362
Provision for (recapture of) loan losses	(13)	(41)	(29)	(80)
Recoveries	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	208	282	208	282
Real Estate [Member] \| Construction [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	22	24	22	48
Provision for (recapture of) loan losses	59	(2)	59	(26)
Recoveries	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	81	22	81	22
Commercial - Other [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	5	7	4	7
Provision for (recapture of) loan losses	(1)	(1)	0	(1)
Recoveries	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	4	6	4	6
SBA Loans [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	0	0	0	0
Provision for (recapture of) loan losses	0	0	0	0
Recoveries	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	0	0	0	0
Consumer [Member]
Allowance for Loan and Lease Losses by Loan Type [Roll Forward]
Beginning balance	0	1	1	1
Provision for (recapture of) loan losses	0	(1)	(1)	(1)
Recoveries	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	$ 0	$ 0	$ 0	$ 0

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

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- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable.

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