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Allowance for Credit Losses - Schedule of Loans for Borrowers Experiencing Financial Difficulties Modified (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	$ 12,658	$ 5,379	$ 45,931	$ 17,955	$ 70,300	$ 23,357
Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	239	0	16,523	0
Post-modification loan balances, payments in default	1,796	448	17,487	2,123
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	10,152	4,791	30,672	15,370
Commercial \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	182	0	15,530	0
Commercial \| Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances					43,695	20,725
Commercial \| Commercial \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances, payments in default	302	28	3,101	142
Commercial real estate \| Construction and development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	568		1,137		1,137	0
Commercial real estate \| Construction and development \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0		0
Post-modification loan balances, payments in default	0	0	568	0
Commercial real estate \| Non-construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	734	196	12,233	196	22,915	243
Commercial real estate \| Non-construction \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	0	0	693	0
Post-modification loan balances, payments in default	1,169	196	13,491	196
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	1,191	392	1,873	1,524	2,538	1,524
Residential real estate \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	57	0	300	0
Post-modification loan balances, payments in default	312	224	312	920
Premium finance receivables—property & casualty \| Premium finance receivables—property & casualty
Financing Receivable, Troubled Debt Restructuring [Line Items]
Post-modification loan balances	13		16	865	$ 15	$ 865
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		0	0
Post-modification loan balances, payments in default	$ 13	$ 0	$ 15	$ 865