Loans and Leases - Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 23,372	$ 23,294
Loans and leases, allowance for losses	60	54
Commercial and Financial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	22,520	22,533
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	602	98
Lease Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 250	$ 663