Loans, Allowance for Credit Losses and Credit Quality - Finance Receivable, Nonaccrual (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Financing Receivable, Nonaccrual [Line Items]
Finance Receivable, Nonaccrual, with allowance	[1]	$ 62,756		$ 62,756		$ 82,660
Financing Receivable, Nonaccrual, No Allowance	[2]	23,841		23,841		18,869
Financing Receivable, Nonaccrual	[1]	86,597		86,597		101,529
Accounts Receivable, Noncurrent, Accrued Interest, Writeoff		173	$ 95	741	$ 594
Commercial And Industrial [Member]
Financing Receivable, Nonaccrual [Line Items]
Finance Receivable, Nonaccrual, with allowance		23,173		23,173		2,802
Financing Receivable, Nonaccrual, No Allowance	[2]	0		0		11,652
Financing Receivable, Nonaccrual		23,173		23,173		14,454
Commercial Real Estate [Member]
Financing Receivable, Nonaccrual [Line Items]
Finance Receivable, Nonaccrual, with allowance		5,375		5,375		67,126
Financing Receivable, Nonaccrual, No Allowance	[2]	23,841		23,841		7,217
Financing Receivable, Nonaccrual		29,216		29,216		74,343
Residential Real Estate [Member]
Financing Receivable, Nonaccrual [Line Items]
Finance Receivable, Nonaccrual, with allowance		14,406		14,406		10,243
Financing Receivable, Nonaccrual, No Allowance	[2]	0		0		0
Financing Receivable, Nonaccrual		14,406		14,406		10,243
Home Equity Loan [Member]
Financing Receivable, Nonaccrual [Line Items]
Finance Receivable, Nonaccrual, with allowance		4,244		4,244		2,479
Financing Receivable, Nonaccrual, No Allowance	[2]	0		0		0
Financing Receivable, Nonaccrual		4,244		4,244		2,479
Consumer - Other [Member]
Financing Receivable, Nonaccrual [Line Items]
Finance Receivable, Nonaccrual, with allowance		42		42		10
Financing Receivable, Nonaccrual, No Allowance	[2]	0		0		0
Financing Receivable, Nonaccrual		42		42		10
Construction Loans [Member]
Financing Receivable, Nonaccrual [Line Items]
Finance Receivable, Nonaccrual, with allowance		15,516		15,516		0
Financing Receivable, Nonaccrual		$ 15,516		$ 15,516		$ 0

[1] (1)Non-accrual balances reported above without an allowance for credit losses are attributable to loans evaluated on an individual basis where it was determined that there was no risk of loss due to sufficient underlying collateral values.

[2] Non-accrual balances reported above without an allowance for credit losses are attributable to loans evaluated on an individual basis where it was determined that there was no risk of loss due to sufficient underlying collateral values.