Loans and Allowance for Credit Losses for Loans - Summary of Collateral Dependent Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 49,355,319	$ 50,210,295
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	9,799,287	9,230,543
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	30,402,196	31,970,047
Commercial real estate | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	26,914,732	28,243,239
Commercial real estate | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,487,464	3,726,808
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	5,684,079	5,569,010
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,469,757	3,440,695
Consumer loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	581,181	559,152
Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	286,599	264,678
Non-accrual loans collateralized	52,200	62,300
Collateral Pledged | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	135,786	96,827
Collateral Pledged | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	130,057	145,419
Collateral Pledged | Commercial real estate | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	114,216	98,785
Collateral Pledged | Commercial real estate | Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	15,841	46,634
Collateral Pledged | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	20,075	21,843
Collateral Pledged | Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	589
Collateral Pledged | Consumer loans | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 681	$ 0