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, 2017	Dec. 31, 2016	Dec. 31, 2015
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 585	$ 656
Collectively evaluated for impairment	3,484	3,947
Total ending allowance balance	4,069	4,603	$ 4,828
Loans:
Loans individually evaluated for impairment	9,305	11,897
Loans collectively evaluated for impairment	329,615	372,160
Gross loans receivable after deferred loan costs and premiums	338,920	384,057
Single family
Ending allowance balance attributable to loans:
Individually evaluated for impairment	100	125
Collectively evaluated for impairment	494	242
Total ending allowance balance	594	367	597
Loans:
Loans individually evaluated for impairment	627	644
Loans collectively evaluated for impairment	110,897	104,688
Gross loans receivable after deferred loan costs and premiums	111,524	105,332
Multi-family
Ending allowance balance attributable to loans:
Individually evaluated for impairment	1
Collectively evaluated for impairment	2,299	2,659
Total ending allowance balance	2,300	2,659	1,658
Loans:
Loans individually evaluated for impairment	333	642
Loans collectively evaluated for impairment	188,585	230,798
Gross loans receivable after deferred loan costs and premiums	188,918	231,440
Commercial real estate
Ending allowance balance attributable to loans:
Collectively evaluated for impairment	71	215
Total ending allowance balance	71	215	469
Loans:
Loans collectively evaluated for impairment	6,096	8,921
Gross loans receivable after deferred loan costs and premiums	6,096	8,921
Church
Ending allowance balance attributable to loans:
Individually evaluated for impairment	479	516
Collectively evaluated for impairment	602	821
Total ending allowance balance	1,081	1,337	2,083
Loans:
Loans individually evaluated for impairment	8,280	10,545
Loans collectively evaluated for impairment	22,232	26,678
Gross loans receivable after deferred loan costs and premiums	30,512	37,223
Construction
Ending allowance balance attributable to loans:
Collectively evaluated for impairment	17	8
Total ending allowance balance	17	8	3
Loans:
Loans collectively evaluated for impairment	1,671	827
Gross loans receivable after deferred loan costs and premiums	1,671	827
Commercial - other
Ending allowance balance attributable to loans:
Individually evaluated for impairment	5	15
Collectively evaluated for impairment	1	2
Total ending allowance balance	6	17	$ 18
Loans:
Loans individually evaluated for impairment	65	66
Loans collectively evaluated for impairment	127	242
Gross loans receivable after deferred loan costs and premiums	192	308
Consumer
Loans:
Loans collectively evaluated for impairment	7	6
Gross loans receivable after deferred loan costs and premiums	$ 7	$ 6

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

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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