Loans and Allowance for Credit Losses - Loans - (Details)	12 Months Ended
Dec. 31, 2021 USD ($) contract loan	Dec. 31, 2020 USD ($) contract loan
Schedule of Available-for-sale Securities [Line Items]
Number of new loans modified as TDRs \| loan	0	0
Number of TDRs accounts \| contract	1	1
Amount of recorded investment in new troubled debt restructurings, totaled	$ 36,000	$ 39,000
Amount of interest that would have been accrued from non performing financial receivable, totaled	$ 14,000,000	$ 201,000,000
Non-performing TDRs
Schedule of Available-for-sale Securities [Line Items]
Number of TDRs accounts \| contract	1	1
Amount of recorded investment in new troubled debt restructurings, totaled	$ 36,139,000	$ 38,711,000
Non-performing TDRs
Schedule of Available-for-sale Securities [Line Items]
Number of TDRs accounts \| contract		1
Amount of recorded investment in new troubled debt restructurings, totaled		$ 39,000
Consumer and Indirect
Schedule of Available-for-sale Securities [Line Items]
Amount of consumer and indirect loans, outstanding	36,139
Amount of consumer and indirect loans, specific reserves	$ 10,331
Number Of Loan Consumer And Indirect Loans \| contract	1

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

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Loans And Leases Receivable Consumer And Indirect Loans

+ References

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Represents loans and leases receivable consumer and indirect loans

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Represents number of loan consumer and indirect loans.

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

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Amount of financing receivable modified as troubled debt restructuring.

+ 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=123577603&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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The gross interest income that would have been recorded in the period on troubled debt restructurings, if the loans had been current in accordance with their original terms and had been outstanding throughout the 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=121585226&loc=d3e18794-111554

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