Loans and Allowance for Credit Losses for Loans - Summary of Collateral Dependent Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 49,877,248	$ 46,917,200
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	9,287,309	8,804,830
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	31,608,833	29,432,868
Commercial real estate | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	27,793,072	25,732,033
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	5,560,356	5,364,550
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,420,750	3,314,952
Consumer | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	535,493	503,884
Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	231,547	258,692
Collateral Pledged | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	77,364	94,433
Collateral Pledged | Commercial real estate | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	138,032	130,199
Collateral Pledged | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	16,151	33,865
Collateral Pledged | Consumer | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 0	$ 195