Loans - Financing Receivables, Modified Loans Past Due in Excess of 90 Days or on Non-Accrual Status at Period-End (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, net of unearned discounts	$ 19,388,206	$ 18,824,251
Combination: Payment Delay and Term Extention | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, net of unearned discounts	32,781		$ 0
Commercial Portfolio Segment [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, net of unearned discounts	6,108,136	5,967,182
Commercial Portfolio Segment [Member] | Combination: Payment Delay and Term Extention
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, net of unearned discounts	28,900		0
Commercial Portfolio Segment [Member] | Combination: Payment Delay and Term Extention | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, net of unearned discounts	13,644		0
Commercial Real Estate Buildings Land And Other Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, net of unearned discounts	7,548,222	$ 7,301,920
Commercial Real Estate Buildings Land And Other Loans [Member] | Combination: Payment Delay and Term Extention | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans, net of unearned discounts	$ 19,137		$ 0