Loans Receivable - Schedule of Information of Impaired Loans by Loan Portfolio Class (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule Of Financial Receivables [Line Items]
Recorded Investment	$ 1,549	$ 1,482
Unpaid Principal Balance	1,549	1,482
Recorded Investment	2,020	1,482
Unpaid Principal Balance	2,020	1,482
Related Allowance	329
Single Family [Member]
Schedule Of Financial Receivables [Line Items]
Recorded Investment	299	1,482
Unpaid Principal Balance	299	1,482
Related Allowance	0	$ 0
Commercial & Industrial [Member]
Schedule Of Financial Receivables [Line Items]
Recorded Investment	46
Unpaid Principal Balance	46
Recorded Investment	471
Unpaid Principal Balance	471
Related Allowance	329
Consumer Secured [Member]
Schedule Of Financial Receivables [Line Items]
Recorded Investment	107
Unpaid Principal Balance	107
Non Owner Occupied [Member]
Schedule Of Financial Receivables [Line Items]
Recorded Investment	1,097
Unpaid Principal Balance	$ 1,097

Impaired Financing Receivable Related Allowance With Allowance Recorded

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- Definition

Impaired Financing Receivable Related Allowance With No Related Allowance

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- Definition

Schedule Of Financial Receivables [Line Items]

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- Definition

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 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 310
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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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- Definition

Unpaid principal balance of impaired financing receivables for which there is 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
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-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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