Age Analysis of Past Due Financing receivables (Details) $ in Thousands		Dec. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan		480	481
Financing Receivable, before Allowance for Credit Loss		$ 14,278,070	$ 13,928,675
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan		29	35
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan		40	46
Number of Loans Total Past Due | loan		549	562
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 23,616	$ 5,934
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		29,433	6,560
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		10,305	29,426
Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		63,354	41,920
Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 14,214,716	$ 13,886,755
Commercial and Industrial [Member]
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan		6	3
Financing Receivable, before Allowance for Credit Loss		$ 1,579,986	$ 1,635,103
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan		1	1
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan		2	3
Number of Loans Total Past Due | loan		9	7
Commercial and Industrial [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 398	$ 49
Commercial and Industrial [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		17,538	175
Commercial and Industrial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		673	23,726
Commercial and Industrial [Member] | Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		18,609	23,950
Commercial and Industrial [Member] | Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 1,561,377	$ 1,611,153
Commercial Real Estate [Member]
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan		8	7
Financing Receivable, before Allowance for Credit Loss		$ 8,041,508	$ 7,760,230
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan		2	5
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan		3	3
Number of Loans Total Past Due | loan		13	15
Commercial Real Estate [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 14,674	$ 2,052
Commercial Real Estate [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		8,419	4,971
Commercial Real Estate [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		7,279	2,977
Commercial Real Estate [Member] | Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		30,372	10,000
Commercial Real Estate [Member] | Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 8,011,136	$ 7,750,230
Construction Loans [Member]
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan		0	0
Financing Receivable, before Allowance for Credit Loss		$ 849,586	$ 1,154,413
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan		0	0
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan		0	0
Number of Loans Total Past Due | loan		0	0
Construction Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 0	$ 0
Construction Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		0	0
Construction Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		0	0
Construction Loans [Member] | Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		0	0
Construction Loans [Member] | Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 849,586	$ 1,154,413
Small Business [Member]
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan		6	12
Financing Receivable, before Allowance for Credit Loss		$ 251,956	$ 219,102
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan		1	3
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan		6	3
Number of Loans Total Past Due | loan		13	18
Small Business [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 400	$ 111
Small Business [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		20	25
Small Business [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		243	5
Small Business [Member] | Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		663	141
Small Business [Member] | Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 251,293	$ 218,961
Residential Real Estate [Member]
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan		24	8
Financing Receivable, before Allowance for Credit Loss		$ 2,424,754	$ 2,035,524
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan		7	8
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan		13	16
Number of Loans Total Past Due | loan		44	32
Residential Real Estate [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 6,216	$ 1,654
Residential Real Estate [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		2,187	1,105
Residential Real Estate [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		1,573	1,725
Residential Real Estate [Member] | Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		9,976	4,484
Residential Real Estate [Member] | Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 2,414,778	$ 2,031,040
Home Equity [Member]
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan		23	19
Financing Receivable, before Allowance for Credit Loss		$ 1,097,626	$ 1,088,750
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan		4	3
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan		10	17
Number of Loans Total Past Due | loan		37	39
Home Equity [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 1,640	$ 1,647
Home Equity [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		1,238	201
Home Equity [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		529	965
Home Equity [Member] | Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		3,407	2,813
Home Equity [Member] | Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss		$ 1,094,219	$ 1,085,937
Consumer Portfolio Segment [Member]
Financing Receivable Impaired [Line Items]
Number Of Financing Receivables Thirty To Fifty Nine Days Past Due | loan	[1]	413	432
Financing Receivable, before Allowance for Credit Loss	[1]	$ 32,654	$ 35,553
Number of Financing Receivables Sixty to Eighty Nine Days Past Due | loan	[1]	14	15
Number Of Financing Receivables Equal To Greater Than Ninety Days | loan	[1]	6	4
Number of Loans Total Past Due | loan	[1]	433	451
Consumer Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss	[1]	$ 288	$ 421
Consumer Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss	[1]	31	83
Consumer Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss	[1]	8	28
Consumer Portfolio Segment [Member] | Financial Asset, Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss	[1]	327	532
Consumer Portfolio Segment [Member] | Financial Asset, Not Past Due
Financing Receivable Impaired [Line Items]
Financing Receivable, before Allowance for Credit Loss	[1]	$ 32,327	$ 35,021

[1] Other consumer portfolio is inclusive of deposit account overdrafts recorded as loan balances.