Loans Receivable: Troubled Debt Restructurings on Financing Receivables (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	11	1
Pre-Modification Outstanding Recorded Investment	$ 2,909	$ 563
Post-Modification Outstanding Recorded Investment	$ 2,909	$ 563
One-to-four family residential \| Principal and Interest with Interest Rate Concession
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	7	1
Pre-Modification Outstanding Recorded Investment	$ 1,360	$ 563
Post-Modification Outstanding Recorded Investment	$ 1,360	$ 563
One-to-four family residential \| Advancement of Maturity Date
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	3	0
Pre-Modification Outstanding Recorded Investment	$ 694	$ 0
Post-Modification Outstanding Recorded Investment	$ 694	$ 0
Commercial Real Estate \| Advancement of Maturity Date
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	1	0
Pre-Modification Outstanding Recorded Investment	$ 855	$ 0
Post-Modification Outstanding Recorded Investment	$ 855	$ 0

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No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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