Loans, Allowance for Credit Losses, and Asset Quality Information - TDRs that Subsequently Defaulted (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) contract	Sep. 30, 2020 USD ($) contract	Sep. 30, 2021 USD ($) contract	Sep. 30, 2020 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0	0	1
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 274
Real estate, mortgage \| Real estate – mortgage – residential (1-4 family) first mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
Real estate, commercial \| Real estate – mortgage – commercial and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	0	0	1
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 274

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No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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- Definition

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

+ References

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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