Loans, Allowance for Credit Losses and Credit Quality - Textual (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2024		Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023		Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses		$ 150,859	[1]	$ 146,948	$ 142,222	$ 140,647	[1]	$ 159,131	$ 152,419
Unfunded commitments		$ 1,400			1,500
Days to be termed as non accrual loans		90 days
Financing Receivable, Nonaccrual	[2]	$ 57,451			54,383
Financing receivable, net deferred costs		6,200			6,400
Financing Receivable, Unamortized Loan Cost (Fee) and Purchase Premium (Discount)		8,400			8,600
Additional commitments to lend to borrowers experiencing financial difficulty party to a loan modification		275				0
Financial Asset, Not Past Due | Aging Loan Modification Member
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Net of Deferred Income						32,692
Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses		20,884	[1]	20,489	19,243	15,142	[1]	36,932	27,559
Financing Receivable, Nonaccrual		17,793			20,188
Commercial And Industrial [Member] | Financial Asset, Not Past Due | Aging Loan Modification Member
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Net of Deferred Income						12,963
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses		80,501	[1]	$ 77,929	74,148	78,396	[1]	$ 76,198	$ 77,799
Financing Receivable, Nonaccrual		$ 23,479			$ 22,952
Commercial Real Estate [Member] | Financial Asset, Not Past Due | Aging Loan Modification Member
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and Leases Receivable, Net of Deferred Income						$ 17,211

[1] Balances of accrued interest receivable excluded from amortized cost and the calculation of allowance for credit losses amounted to $59.2 million and $54.0 million as of June 30, 2024 and June 30, 2023, respectively.

[2] (1)Nonaccrual 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.