Allowance for Credit Losses - Schedule of Loans for Borrowers Experiencing Financial Difficulties Modified (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	$ 3,122	$ 40,729	$ 25,976
Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	883	35,304
Post-modification loan balances, payments in default	1,010	945
Commercial \| Commercial, industrial and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	1,629	37,474	16,011
Commercial \| Commercial, industrial and other \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0	35,265
Post-modification loan balances, payments in default	244	2
Commercial real estate \| Construction and development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances		0	2,495
Commercial real estate \| Construction and development \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances, payments in default	0	0
Commercial real estate \| Non-construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	1,176	1,333	6,161
Commercial real estate \| Non-construction \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	883	39
Post-modification loan balances, payments in default	603	828
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	98	203	616
Home equity \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0	0
Post-modification loan balances, payments in default	19	104
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	218	1,708	612
Residential real estate \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0	0
Post-modification loan balances, payments in default	144	0
Premium finance receivables \| Property and casualty insurance loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	1	11	$ 81
Premium finance receivables \| Property and casualty insurance loans \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0	0
Post-modification loan balances, payments in default	$ 0	$ 11

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 44
-Subparagraph (a)(2)
-Publisher FASB
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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Topic 310
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-Topic 310
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-SubTopic 10
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