Loans - Accrued Interest (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	$ 84,274
Commercial | Commercial, financial, and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	55,215
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	11,233
Consumer | Consumer Real Estate (a)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	16,154
Consumer | Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest	$ 1,672