Allowance for Credit Losses and Credit Quality of Loans, Allowance for Credit Losses on Off-Balance Sheet Credit Exposures (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Allowance for Credit Losses and Credit Quality of Loans [Abstract]
Allowance for credit losses	$ 119,500	$ 120,500	$ 114,601	$ 100,400	$ 119,500	$ 114,601	$ 114,400
Unfunded Loan Commitments [Member]
Allowance for Credit Losses and Credit Quality of Loans [Abstract]
Allowance for credit losses	4,600				4,600		$ 5,100
Reserve for credit losses	$ 300	$ (400)		$ 500	$ (600)	$ (300)
Salisbury acquisition-related provision for credit losses			$ 800