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, 2018	Dec. 31, 2017
Impaired loans
Average Recorded Investment	$ 8,904	$ 10,958
Cash Basis Interest Income Recognized	455	875
Foregone interest income if impaired loans had performed according to terms	280	126
Single family
Impaired loans
Average Recorded Investment	618	636
Cash Basis Interest Income Recognized	30	28
Multi-family
Impaired loans
Average Recorded Investment	329	589
Cash Basis Interest Income Recognized	23	44
Commercial real estate
Impaired loans
Average Recorded Investment		305
Cash Basis Interest Income Recognized		104
Church
Impaired loans
Average Recorded Investment	7,893	9,363
Cash Basis Interest Income Recognized	398	693
Commercial - other
Impaired loans
Average Recorded Investment	64	65
Cash Basis Interest Income Recognized	$ 4	$ 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554

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