Loans and Allowance for Loan Losses - Schedule of Current, Accruing Past Due, and Non-Accrual Loans by Portfolio Class (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	$ 42,609,028	$ 43,404,490
Non-accrual with an ALL	271,174	216,667
Non-accrual without an ALL	37,990	71,510
Accrued interest receivable	$ 217,100	$ 256,300
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Deferred loan costs (fees)	$ (34,100)	$ (35,900)
Commercial & Industrial
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	22,331,129	22,598,493
Non-accrual with an ALL	119,264	137,184
Non-accrual without an ALL	37,990	44,056
Commercial & Industrial \| Commercial, financial, and agricultural
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	14,498,992	14,459,345
Non-accrual with an ALL	98,145	66,400
Non-accrual without an ALL	24,729	23,470
Commercial & Industrial \| Owner-occupied
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	7,832,137	8,139,148
Non-accrual with an ALL	21,119	70,784
Non-accrual without an ALL	13,261	20,586
Commercial & Industrial \| Senior Housing Loans
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	2,940,000	3,280,000
Commercial Real Estate
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	12,014,619	12,316,758
Non-accrual with an ALL	77,804	16,205
Non-accrual without an ALL	0	27,425
Commercial Real Estate \| Investment properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	11,181,204	11,363,304
Non-accrual with an ALL	74,030	12,796
Non-accrual without an ALL	0	26,974
Commercial Real Estate \| 1-4 family properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	545,918	598,502
Non-accrual with an ALL	2,385	2,605
Non-accrual without an ALL	0	451
Commercial Real Estate \| Land and development
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	287,497	354,952
Non-accrual with an ALL	1,389	804
Non-accrual without an ALL	0	0
Consumer
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	8,263,280	8,489,239
Non-accrual with an ALL	74,106	63,278
Non-accrual without an ALL	0	29
Consumer \| Consumer mortgages
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	5,288,776	5,411,723
Non-accrual with an ALL	50,834	46,108
Non-accrual without an ALL	0	0
Consumer \| Home equity
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,831,287	1,807,399
Non-accrual with an ALL	17,365	10,473
Non-accrual without an ALL	0	0
Consumer \| Credit cards
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	185,871	194,141
Non-accrual with an ALL	0	0
Non-accrual without an ALL	0	0
Consumer \| Other consumer loans
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	957,346	1,075,976
Non-accrual with an ALL	5,907	6,697
Non-accrual without an ALL	0	29
Current
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	42,190,986	43,057,214
Current \| Commercial & Industrial
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	22,106,891	22,396,987
Current \| Commercial & Industrial \| Commercial, financial, and agricultural
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	14,352,839	14,355,414
Current \| Commercial & Industrial \| Owner-occupied
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	7,754,052	8,041,573
Current \| Commercial Real Estate
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	11,931,858	12,271,352
Current \| Commercial Real Estate \| Investment properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	11,105,168	11,322,516
Current \| Commercial Real Estate \| 1-4 family properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	541,897	595,359
Current \| Commercial Real Estate \| Land and development
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	284,793	353,477
Current \| Consumer
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	8,152,237	8,388,875
Current \| Consumer \| Consumer mortgages
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	5,228,580	5,359,153
Current \| Consumer \| Home equity
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,800,614	1,785,836
Current \| Consumer \| Credit cards
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	182,435	190,299
Current \| Consumer \| Other consumer loans
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	940,608	1,053,587
Accruing 30-89 Days Past Due
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	60,286	54,046
Accruing 30-89 Days Past Due \| Commercial & Industrial
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	20,647	18,320
Accruing 30-89 Days Past Due \| Commercial & Industrial \| Commercial, financial, and agricultural
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	12,947	12,264
Accruing 30-89 Days Past Due \| Commercial & Industrial \| Owner-occupied
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	7,700	6,056
Accruing 30-89 Days Past Due \| Commercial Real Estate
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	4,755	1,498
Accruing 30-89 Days Past Due \| Commercial Real Estate \| Investment properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	2,006	740
Accruing 30-89 Days Past Due \| Commercial Real Estate \| 1-4 family properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,636	87
Accruing 30-89 Days Past Due \| Commercial Real Estate \| Land and development
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,113	671
Accruing 30-89 Days Past Due \| Consumer
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	34,884	34,228
Accruing 30-89 Days Past Due \| Consumer \| Consumer mortgages
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	9,362	6,462
Accruing 30-89 Days Past Due \| Consumer \| Home equity
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	13,131	10,374
Accruing 30-89 Days Past Due \| Consumer \| Credit cards
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,573	1,818
Accruing 30-89 Days Past Due \| Consumer \| Other consumer loans
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	10,818	15,574
Accruing 90 Days or Greater Past Due
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	48,592	5,053
Accruing 90 Days or Greater Past Due \| Commercial & Industrial
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	46,337	1,946
Accruing 90 Days or Greater Past Due \| Commercial & Industrial \| Commercial, financial, and agricultural
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	10,332	1,797
Accruing 90 Days or Greater Past Due \| Commercial & Industrial \| Owner-occupied
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	36,005	149
Accruing 90 Days or Greater Past Due \| Commercial Real Estate
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	202	278
Accruing 90 Days or Greater Past Due \| Commercial Real Estate \| Investment properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	0	278
Accruing 90 Days or Greater Past Due \| Commercial Real Estate \| 1-4 family properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	0	0
Accruing 90 Days or Greater Past Due \| Commercial Real Estate \| Land and development
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	202	0
Accruing 90 Days or Greater Past Due \| Consumer
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	2,053	2,829
Accruing 90 Days or Greater Past Due \| Consumer \| Consumer mortgages
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	0	0
Accruing 90 Days or Greater Past Due \| Consumer \| Home equity
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	177	716
Accruing 90 Days or Greater Past Due \| Consumer \| Credit cards
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,863	2,024
Accruing 90 Days or Greater Past Due \| Consumer \| Other consumer loans
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	13	89
Total Accruing Past Due
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	108,878	59,099
Total Accruing Past Due \| Commercial & Industrial
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	66,984	20,266
Total Accruing Past Due \| Commercial & Industrial \| Commercial, financial, and agricultural
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	23,279	14,061
Total Accruing Past Due \| Commercial & Industrial \| Owner-occupied
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	43,705	6,205
Total Accruing Past Due \| Commercial Real Estate
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	4,957	1,776
Total Accruing Past Due \| Commercial Real Estate \| Investment properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	2,006	1,018
Total Accruing Past Due \| Commercial Real Estate \| 1-4 family properties
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,636	87
Total Accruing Past Due \| Commercial Real Estate \| Land and development
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	1,315	671
Total Accruing Past Due \| Consumer
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	36,937	37,057
Total Accruing Past Due \| Consumer \| Consumer mortgages
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	9,362	6,462
Total Accruing Past Due \| Consumer \| Home equity
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	13,308	11,090
Total Accruing Past Due \| Consumer \| Credit cards
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	3,436	3,842
Total Accruing Past Due \| Consumer \| Other consumer loans
Financing Receivable, Nonaccrual [Line Items]
Loans, net of deferred fees and costs	$ 10,831	$ 15,663

Loans and Allowance for Loan Losses - Schedule of Current, Accruing Past Due, and Non-Accrual Loans by Portfolio Class (Details) - USD ($)
$ in Thousands