Fair Value Measurements - Quantitative Information About Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Collateral-dependent impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 2,404	$ 71
Valuation Technique	Market comparable properties	Market comparable properties
Unobservable inputs	Marketability discount	Comparability adjustments
Collateral-dependent impaired loans \| Maximum \| Market comparable properties [Member] \| Marketability discount [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range	25.00%
Collateral-dependent impaired loans \| Maximum \| Market comparable properties [Member] \| Comparability Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range		10.00%
Collateral-dependent impaired loans \| Minimum \| Market comparable properties [Member] \| Marketability discount [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range	10.00%
Collateral-dependent impaired loans \| Minimum \| Market comparable properties [Member] \| Comparability Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range		5.00%
Foreclosed assets held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 0	$ 0
Valuation Technique	Market comparable properties	Market comparable properties
Unobservable inputs	Marketability discount	Marketability discount
Foreclosed assets held for sale \| Maximum \| Market comparable properties [Member] \| Marketability discount [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range	35.00%	35.00%
Foreclosed assets held for sale \| Minimum \| Market comparable properties [Member] \| Marketability discount [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Range	10.00%	10.00%

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- Definition

Fair value measurement unobservable inputs range weighted average.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Description of the valuation processes in place for fair value measurements categorized within Level 3 of the fair value hierarchy.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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