Loans Receivable Held for Investment - Activity in the Allowance for Loan Losses by Loan Type (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Allowance for loan losses:
Beginning balance	$ 4,069	$ 4,603
Provision for (recapture of) loan losses	(1,254)	(1,100)
Recoveries	114	566
Ending balance	2,929	4,069
Single family
Allowance for loan losses:
Beginning balance	594	367
Provision for (recapture of) loan losses	(225)	197
Recoveries		30
Ending balance	369	594
Multi-family
Allowance for loan losses:
Beginning balance	2,300	2,659
Provision for (recapture of) loan losses	(420)	(359)
Ending balance	1,880	2,300
Commercial real estate
Allowance for loan losses:
Beginning balance	71	215
Provision for (recapture of) loan losses	(19)	(144)
Ending balance	52	71
Church
Allowance for loan losses:
Beginning balance	1,081	1,337
Provision for (recapture of) loan losses	(592)	(792)
Recoveries	114	536
Ending balance	603	1,081
Construction
Allowance for loan losses:
Beginning balance	17	8
Provision for (recapture of) loan losses	2	9
Ending balance	19	17
Commercial - other
Allowance for loan losses:
Beginning balance	6	17
Provision for (recapture of) loan losses		(11)
Ending balance	$ 6	$ 6

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

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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