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Loans and Allowance for Credit Losses - Narrative (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan
Financing Receivable, Allowance for Credit Loss [Line Items]
Unearned income	$ 7.4	$ 7.5
Purchase accounting fair value adjustments	$ 4.4	$ 4.7
Threshold period of satisfactory performance for troubled debt restructuring to be restored to accruing status	6 months
Number of troubled debt restructuring loans returned to accruing status | loan		1
Reclassified to accruing status		$ 0.2
Number of commitments to lend additional funds on TDRs | loan		16
Commitments to lend additional funds on TDRs		$ 0.4
Default
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of defaulted TDRs that were restructured within the last twelve months prior to defaulting | loan	0

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- Definition

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Acquired Receivable, Fair Value

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Commitment To Lend Additional Funds

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- Definition

Financial Receivable, Trouble Debt Restructuring, Reclassified To Accruing Status

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Number of troubled debt restructuring loans returned back to accruing status.

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Threshold Period of Satisfactory Payments to Remove from Nonaccrual Status

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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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
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

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Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481598/310-20-45-1

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-SubTopic 20
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481569/310-20-50-3

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