Loans Receivable Held for Investment - Activity in the Allowance for Loan Losses by Loan Type (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Allowance for loan losses:
Beginning balance	$ 3,182	$ 2,929
Provision for (recapture of) loan losses	29	(190)
Recoveries		190
Ending balance	3,211	2,929
Single family
Allowance for loan losses:
Beginning balance	312	369
Provision for (recapture of) loan losses	(4)	(22)
Ending balance	308	347
Multi-family
Allowance for loan losses:
Beginning balance	2,319	1,880
Provision for (recapture of) loan losses	89	110
Ending balance	2,408	1,990
Commercial real estate
Allowance for loan losses:
Beginning balance	133	52
Provision for (recapture of) loan losses	7	10
Ending balance	140	62
Church
Allowance for loan losses:
Beginning balance	362	603
Provision for (recapture of) loan losses	(39)	(286)
Recoveries		190
Ending balance	323	507
Construction
Allowance for loan losses:
Beginning balance	48	19
Provision for (recapture of) loan losses	(24)	(1)
Ending balance	24	18
Commercial - other
Allowance for loan losses:
Beginning balance	7	6
Provision for (recapture of) loan losses		(1)
Ending balance	7	$ 5
Consumer
Allowance for loan losses:
Beginning balance	1
Ending balance	$ 1