Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2025 USD ($) segment subsidiary	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Property, Plant and Equipment
Other adjustments		$ 600,000	$ 300,000
Impairment losses	$ 5,100,000
Number of significant subsidiaries | subsidiary	1
Income tax examination, penalties	$ 0	0	0
Cash on deposit with Federal Reserve Bank	951,400,000	518,200,000
Federal Reserve Bank stock	95,000,000.0
Federal Home Loan Bank stock	10,700,000	81,300,000
Advertising expense	1,700,000	700,000	900,000
Capitalized Computer Software, Gross	3,500,000	2,900,000
Loans and Leases Receivable Disclosure [Line Items]
Accrued interest receivable	102,600,000	116,800,000
Accrued Investment Income Receivable	27,800,000	29,600,000
Hosting Arrangement, Service Contract, Implementation Cost, Expense, Amortization	$ 2,200,000	2,200,000
Number of operating segments | segment	1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
APIC, Share-Based Payment Arrangement, Increase for Cost Recognition	$ 13,300,000	11,800,000	4,700,000
Total investment securities	$ 700,000	1,200,000
Buildings and improvements | Minimum
Property, Plant and Equipment
Estimated useful lives	5 years
Buildings and improvements | Maximum [Member]
Property, Plant and Equipment
Estimated useful lives	45 years
Furniture and equipment | Minimum
Property, Plant and Equipment
Estimated useful lives	3 years
Furniture and equipment | Maximum [Member]
Property, Plant and Equipment
Estimated useful lives	15 years
Loans
Loans and Leases Receivable Disclosure [Line Items]
Accrued interest receivable	$ 73,400,000	84,800,000
Common Stock Including Additional Paid in Capital [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
APIC, Share-Based Payment Arrangement, Increase for Cost Recognition	13,300,000	11,800,000	$ 4,700,000
Subsidiaries | Notes payable
Variable Interest Entity [Line Items]
Long Term Debt, Acquired or Assumed	$ 19,400,000	$ 28,400,000