Commitments and Contingent Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Unadvanced Commitment on Impaired Loan
Schedule of Commitments [Line Items]
Estimated losses attributable to unadvanced commitments on impaired loans	$ 6,400	$ 6,000
Commitments to extend credit
Schedule of Commitments [Line Items]
Off-balance sheet financial instruments, contractual amounts	3,054,916	2,866,028
Commitments to extend credit | Fixed Rate Loan Commitment
Schedule of Commitments [Line Items]
Off-balance sheet financial instruments, contractual amounts	111,600	124,900
Letters of credit
Schedule of Commitments [Line Items]
Off-balance sheet financial instruments, contractual amounts	$ 111,301	$ 102,884
Letters of credit | Maximum
Schedule of Commitments [Line Items]
Remaining term	4 years 3 months
Letters of credit | Minimum
Schedule of Commitments [Line Items]
Remaining term	1 month