Loans and Leases - Loan and Lease Balances (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans and Leases Receivable Disclosure
Loans and leases	$ 35,921,614	$ 34,497,464
Loan and lease adjustments	(177,800)	(201,500)
Commercial
Loans and Leases Receivable Disclosure
Loans and leases	24,522,845	23,276,341
Commercial | Commercial and industrial
Loans and Leases Receivable Disclosure
Loans and leases	12,326,943	11,439,602
Commercial | Commercial real estate
Loans and Leases Receivable Disclosure
Loans and leases	9,486,904	9,136,870
Commercial | Lease financing
Loans and Leases Receivable Disclosure
Loans and leases	2,708,998	2,699,869
Consumer
Loans and Leases Receivable Disclosure
Loans and leases	11,398,769	11,221,123
Consumer | Residential mortgage
Loans and Leases Receivable Disclosure
Loans and leases	6,435,314	6,179,805
Consumer | Consumer installment
Loans and Leases Receivable Disclosure
Loans and leases	1,509,953	1,542,411
Consumer | Home equity
Loans and Leases Receivable Disclosure
Loans and leases	$ 3,453,502	$ 3,498,907