Loans Receivable Held for Investment - Allowance for Loan Losses and Recorded Investment in Loans by Type of Loans and Based on Impairment Method (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 186	$ 227
Collectively evaluated for impairment	2,743	2,702
Total ending allowance balance	2,929	2,929	$ 4,183	$ 4,069
Loans:
Loans individually evaluated for impairment	5,171	6,380
Loans collectively evaluated for impairment	362,773	352,105
Gross loans receivable after deferred loan costs and premiums	367,944	358,485
Single family
Ending allowance balance attributable to loans:
Individually evaluated for impairment	38	53
Collectively evaluated for impairment	309	316
Total ending allowance balance	347	369	588	594
Loans:
Loans individually evaluated for impairment	606	610
Loans collectively evaluated for impairment	88,762	91,567
Gross loans receivable after deferred loan costs and premiums	89,368	92,177
Multi-family
Ending allowance balance attributable to loans:
Collectively evaluated for impairment	1,990	1,880
Total ending allowance balance	1,990	1,880	2,508	2,300
Loans:
Loans individually evaluated for impairment	321	323
Loans collectively evaluated for impairment	246,683	232,986
Gross loans receivable after deferred loan costs and premiums	247,004	233,309
Commercial real estate
Ending allowance balance attributable to loans:
Collectively evaluated for impairment	62	52
Total ending allowance balance	62	52	65	71
Loans:
Loans collectively evaluated for impairment	6,894	5,800
Gross loans receivable after deferred loan costs and premiums	6,894	5,800
Church
Ending allowance balance attributable to loans:
Individually evaluated for impairment	145	170
Collectively evaluated for impairment	362	433
Total ending allowance balance	507	603	1,005	1,081
Loans:
Loans individually evaluated for impairment	4,181	5,383
Loans collectively evaluated for impairment	18,503	19,713
Gross loans receivable after deferred loan costs and premiums	22,684	25,096
Construction
Ending allowance balance attributable to loans:
Collectively evaluated for impairment	18	19
Total ending allowance balance	18	19	11	17
Loans:
Loans collectively evaluated for impairment	1,745	1,872
Gross loans receivable after deferred loan costs and premiums	1,745	1,872
Commercial - other
Ending allowance balance attributable to loans:
Individually evaluated for impairment	3	4
Collectively evaluated for impairment	2	2
Total ending allowance balance	5	6	$ 6	$ 6
Loans:
Loans individually evaluated for impairment	63	64
Loans collectively evaluated for impairment	171	162
Gross loans receivable after deferred loan costs and premiums	234	226
Consumer
Loans:
Loans collectively evaluated for impairment	15	5
Gross loans receivable after deferred loan costs and premiums	$ 15	$ 5

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- Definition

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

+ References

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-Publisher FASB
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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually 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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- Definition

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.

+ References

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-Publisher FASB
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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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