Loans (Schedule Of Loan Portfolio, Net Of Unearned Income) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 85,266	$ 82,963	$ 83,152
Loans and Leases Receivable, Deferred Income	678	234
Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	42,870	39,971
Commercial Real Estate Mortgage - Owner-Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	5,405	5,537
Commercial Real Estate Construction - Owner-Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	300	331
Commercial Investor Real Estate Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	5,394	4,936
Commercial Investor Real Estate Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,869	1,621
Residential First Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	16,575	14,485
Home Equity Lines of Credit[Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	4,539	5,300
Home Equity Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	2,713	3,084
Indirect-vehicles [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	934	1,812
Indirect-other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	2,431	3,249
Consumer Credit Card Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,213	1,387
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,023	1,250
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	48,575	45,839	45,215
Total Investor Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	7,263	6,557	6,436
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 29,428	$ 30,567	$ 31,501