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
Mar. 31, 2017	Mar. 31, 2016
Impaired loans
Average Recorded Investment	$ 12,150	$ 15,348
Cash Basis Interest Income Recognized	246	230
Foregone interest income if impaired loans had performed according to terms	46	119
Single family
Impaired loans
Average Recorded Investment	642	951
Cash Basis Interest Income Recognized	7	7
Multi-family
Impaired loans
Average Recorded Investment	640	1,206
Cash Basis Interest Income Recognized	11	41
Commercial real estate
Impaired loans
Average Recorded Investment	331	1,933
Cash Basis Interest Income Recognized		56
Church
Impaired loans
Average Recorded Investment	10,471	11,191
Cash Basis Interest Income Recognized	227	126
Commercial - other
Impaired loans
Average Recorded Investment	66	$ 67
Cash Basis Interest Income Recognized	$ 1

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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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