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	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 227	$ 585
Collectively evaluated for impairment	2,702	3,484
Total ending allowance balance	2,929	4,069	$ 4,603
Loans:
Loans individually evaluated for impairment	6,380	9,305
Loans collectively evaluated for impairment	352,105	329,615
Gross loans receivable after deferred loan costs and premiums	358,485	338,920
Single family
Ending allowance balance attributable to loans:
Individually evaluated for impairment	53	100
Collectively evaluated for impairment	316	494
Total ending allowance balance	369	594	367
Loans:
Loans individually evaluated for impairment	610	627
Loans collectively evaluated for impairment	91,567	110,897
Gross loans receivable after deferred loan costs and premiums	92,177	111,524
Multi-family
Ending allowance balance attributable to loans:
Individually evaluated for impairment		1
Collectively evaluated for impairment	1,880	2,299
Total ending allowance balance	1,880	2,300	2,659
Loans:
Loans individually evaluated for impairment	323	333
Loans collectively evaluated for impairment	232,986	188,585
Gross loans receivable after deferred loan costs and premiums	233,309	188,918
Commercial real estate
Ending allowance balance attributable to loans:
Collectively evaluated for impairment	52	71
Total ending allowance balance	52	71	215
Loans:
Loans collectively evaluated for impairment	5,800	6,096
Gross loans receivable after deferred loan costs and premiums	5,800	6,096
Church
Ending allowance balance attributable to loans:
Individually evaluated for impairment	170	479
Collectively evaluated for impairment	433	602
Total ending allowance balance	603	1,081	1,337
Loans:
Loans individually evaluated for impairment	5,383	8,280
Loans collectively evaluated for impairment	19,713	22,232
Gross loans receivable after deferred loan costs and premiums	25,096	30,512
Construction
Ending allowance balance attributable to loans:
Collectively evaluated for impairment	19	17
Total ending allowance balance	19	17	8
Loans:
Loans collectively evaluated for impairment	1,872	1,671
Gross loans receivable after deferred loan costs and premiums	1,872	1,671
Commercial - other
Ending allowance balance attributable to loans:
Individually evaluated for impairment	4	5
Collectively evaluated for impairment	2	1
Total ending allowance balance	6	6	$ 17
Loans:
Loans individually evaluated for impairment	64	65
Loans collectively evaluated for impairment	162	127
Gross loans receivable after deferred loan costs and premiums	226	192
Consumer
Loans:
Loans collectively evaluated for impairment	5	7
Gross loans receivable after deferred loan costs and premiums	$ 5	$ 7

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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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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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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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