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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, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	$ 34,426	$ 19,821	$ 72,079	$ 32,117
Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	14,897	0
Post-modification loan balances, payments in default	14,373	827
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	20,642	18,948
Commercial \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	14,897	0
Commercial \| Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances			45,738	29,487
Commercial \| Commercial \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances, payments in default	589	117
Commercial real estate \| Construction and development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	594		594	701
Commercial real estate \| Construction and development \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0
Post-modification loan balances, payments in default	594	0
Commercial real estate \| Non-construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	13,178		24,462	379
Commercial real estate \| Non-construction \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0
Post-modification loan balances, payments in default	13,178	0
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances			117	0
Home equity \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances, payments in default	0	0
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances		873	1,156	874
Residential real estate \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances		0
Post-modification loan balances, payments in default	0	710
Premium finance receivables—property & casualty \| Premium finance receivables—property & casualty
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	12		$ 12	$ 676
Premium finance receivables—property & casualty \| Premium finance receivables—property & casualty \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0
Post-modification loan balances, payments in default	$ 12	$ 0