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Loans and Allowance for Credit Losses - Troubled Debt Restructuring and CARES Act Narrative (Details)	12 Months Ended			22 Months Ended
	Dec. 31, 2021 USD ($) loan borrowingRelationship	Dec. 31, 2020 USD ($) borrowingRelationship loan	Dec. 31, 2019 USD ($) loan	Dec. 31, 2021 USD ($) loan borrowingRelationship
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans removed from TDR designation | loan		0	1
Loan modifications under CARES Act during period | loan				269
Loans modified under CARES Act during period, value				$ 402,900,000
Loan modifications under CARES Act, additional relief, number of borrowing relationships | borrowingRelationship	2	21		2
Loan modifications under CARES Act, additional relief | loan	3	29		3
Loan modifications under CARES Act, additional relief, value	$ 23,600,000	$ 71,000,000		$ 23,600,000
Weighted average loan-to-value ratio	44.00%
Total of TDR loans charged-off within previous 12 months, value	$ 0	$ 0	$ 0
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans removed from TDR designation | loan	1
Recorded investment of loans removed from TDR resignation	$ 2,000		$ 3,000
Residential loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded investment of loans removed from TDR resignation	$ 600,000

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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