Loans Receivable Held for Investment - Average of Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Impaired loans
Average Recorded Investment	$ 13,669	$ 20,043
Cash Basis Interest Income Recognized	1,173	1,171
Foregone interest income if impaired loans had performed according to terms	69	708
Single family
Impaired loans
Average Recorded Investment	824	1,260
Cash Basis Interest Income Recognized	253	140
Multi-family
Impaired loans
Average Recorded Investment	916	1,912
Cash Basis Interest Income Recognized	155	136
Commercial real estate
Impaired loans
Average Recorded Investment	983	3,162
Cash Basis Interest Income Recognized	271	275
Church
Impaired loans
Average Recorded Investment	10,880	13,630
Cash Basis Interest Income Recognized	489	614
Commercial - other
Impaired loans
Average Recorded Investment	66	79
Cash Basis Interest Income Recognized	$ 5	$ 6

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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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