Loans Receivable Held for Investment - Average of Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Impaired loans
Average Recorded Investment	$ 11,956	$ 14,620	$ 11,909	$ 14,994
Cash Basis Interest Income Recognized	233	352	479	582
Foregone interest income if impaired loans had performed according to terms	28	0	74	97
Single family
Impaired loans
Average Recorded Investment	638	927	640	939
Cash Basis Interest Income Recognized	7	7	14	14
Multi-family
Impaired loans
Average Recorded Investment	635	966	638	1,102
Cash Basis Interest Income Recognized	12	11	23	52
Commercial real estate
Impaired loans
Average Recorded Investment	992	1,746	567	1,825
Cash Basis Interest Income Recognized	104	211	104	267
Church
Impaired loans
Average Recorded Investment	9,625	10,915	9,998	11,061
Cash Basis Interest Income Recognized	109	121	336	247
Commercial - other
Impaired loans
Average Recorded Investment	66	66	66	67
Cash Basis Interest Income Recognized	$ 1	$ 2	$ 2	$ 2

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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