Loans Past Due Status (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2025	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	$ 30,607,605	$ 30,607,605	$ 29,768,586
Financing Receivable, Nonaccrual	112,999	112,999	123,260
Nonaccrual Loans, Current Portion	$ 33,300	$ 33,300	$ 52,400
Percent of current nonaccrual loans	29.00%	29.00%	42.00%
Financing Receivable, Nonaccrual, Interest Income	$ 0	$ 0	$ 0
Financing Receivable, Nonaccrual, No Allowance	21,400	21,400	23,800
Commercial and Industrial Sector
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	11,281,964	11,281,964	10,573,741
Financing Receivable, Nonaccrual	6,945	6,945	19,084
Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	1,101,501	1,101,501	1,143,741
Financing Receivable, Nonaccrual	0	0	1,501
Commercial And Business Lending [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	12,383,465	12,383,465	11,717,483
Financing Receivable, Nonaccrual	6,945	6,945	20,585
Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	5,370,422	5,370,422	5,227,975
Financing Receivable, Nonaccrual	15,805	15,805	16,705
Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	1,950,267	1,950,267	1,982,632
Financing Receivable, Nonaccrual	146	146	30
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	7,320,689	7,320,689	7,210,607
Financing Receivable, Nonaccrual	15,950	15,950	16,735
Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	19,704,154	19,704,154	18,928,090
Financing Receivable, Nonaccrual	22,895	22,895	37,320
Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	6,949,387	6,949,387	7,047,541
Financing Receivable, Nonaccrual	73,817	73,817	70,038
Automobile Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	2,969,495	2,969,495	2,810,220
Financing Receivable, Nonaccrual	8,004	8,004	7,402
Home Equity Line of Credit [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	676,208	676,208	664,252
Financing Receivable, Nonaccrual	8,201	8,201	8,378
Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	308,361	308,361	318,483
Financing Receivable, Nonaccrual	82	82	122
Consumer Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	10,903,451	10,903,451	10,840,496
Financing Receivable, Nonaccrual	90,104	90,104	85,941
Financial Asset, Not Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	30,442,282	30,442,282	29,565,335
Financial Asset, Not Past Due [Member] | Commercial and Industrial Sector
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	11,271,869	11,271,869	10,552,756
Financial Asset, Not Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	1,095,873	1,095,873	1,140,607
Financial Asset, Not Past Due [Member] | Commercial And Business Lending [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	12,367,742	12,367,742	11,693,363
Financial Asset, Not Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	5,342,011	5,342,011	5,174,879
Financial Asset, Not Past Due [Member] | Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	1,950,031	1,950,031	1,982,581
Financial Asset, Not Past Due [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	7,292,042	7,292,042	7,157,460
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	19,659,784	19,659,784	18,850,823
Financial Asset, Not Past Due [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	6,866,825	6,866,825	6,962,610
Financial Asset, Not Past Due [Member] | Automobile Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	2,948,341	2,948,341	2,787,967
Financial Asset, Not Past Due [Member] | Home Equity Line of Credit [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	663,668	663,668	651,248
Financial Asset, Not Past Due [Member] | Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	303,664	303,664	312,687
Financial Asset, Not Past Due [Member] | Consumer Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	10,782,499	10,782,499	10,714,512
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	31,561	31,561	40,961
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial and Industrial Sector
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	555	555	899
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	5,258	5,258	1,533
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial And Business Lending [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	5,813	5,813	2,432
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	587	587	5,117
Financial Asset, 30 to 59 Days Past Due [Member] | Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	90	90	21
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	677	677	5,138
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	6,490	6,490	7,570
Financial Asset, 30 to 59 Days Past Due [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	8,710	8,710	14,731
Financial Asset, 30 to 59 Days Past Due [Member] | Automobile Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	11,142	11,142	12,588
Financial Asset, 30 to 59 Days Past Due [Member] | Home Equity Line of Credit [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	3,629	3,629	4,181
Financial Asset, 30 to 59 Days Past Due [Member] | Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	1,591	1,591	1,892
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	25,072	25,072	33,391
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	6,602	6,602	35,841
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial and Industrial Sector
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	2,039	2,039	361
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	370	370	101
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial And Business Lending [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	2,409	2,409	462
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	455	455	31,274
Financial Asset, 60 to 89 Days Past Due [Member] | Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	0	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	455	455	31,274
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	2,864	2,864	31,736
Financial Asset, 60 to 89 Days Past Due [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	34	34	162
Financial Asset, 60 to 89 Days Past Due [Member] | Automobile Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	2,007	2,007	2,262
Financial Asset, 60 to 89 Days Past Due [Member] | Home Equity Line of Credit [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	709	709	445
Financial Asset, 60 to 89 Days Past Due [Member] | Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	987	987	1,236
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	3,738	3,738	4,105
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	14,160	14,160	3,189
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial and Industrial Sector
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	558	558	642
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Owner Occupied Portfolio [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	0	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial And Business Lending [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	558	558	642
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Investor Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	11,565	11,565	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	0	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	11,565	11,565	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	12,123	12,123	642
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Residential Mortgage [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	0	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Automobile Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	0	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Home Equity Line of Credit [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	0	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	2,038	2,038	2,547
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Consumer Loan [Member]
Financing Receivable, Past Due [Line Items]
Loans and Leases Receivable, Net of Deferred Income, Total	$ 2,038	$ 2,038	$ 2,547