Loans And Allowance For Loan Losses (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Loans And Allowance For Loan Losses [Abstract]
Loans To Principal Holders (over 10% ownership in the Company's stock)	$ 0
Unfunded Loan Commitments	8,400,000,000
Unused Approved Credit Card Lines of Credit	3,500,000,000
Loans pledged at the Federal Home Loan Bank as collateral for borrowings and letters of credit obtained to secure public deposits	3,600,000,000
Loans pledged at the Federal Reserve Bank as collateral for discount window borrowings	1,300,000,000
Net Investment in Direct Financing and Sales Type Leases	413,000,000	368,800,000
Capital Leases, Net Investment in Sales Type Leases, Deferred Income	26,400,000	25,100,000
Property Subject to or Available for Operating Lease, Net	22,800,000	24,400,000
Credit quality personal real estate loans excluded	244,300,000	244,300,000
Personal real estate loans excluded from table, as a percentage of Personal Banking portfolio	6.00%	6.00%
Restructured loans	64,445,000
Restructured loans on non-accrual status	24,100,000
Accruing Restructured Loans	40,313,000	58,822,000
Restructured loans performing under their modified terms	21,800,000	38,200,000
Aggregate restructured credit card loans held	10,400,000	11,800,000
Restructured Loans due to Bankruptcy	8,100,000	8,800,000
Decrease in interest income resulting from modification to credit card loans	(1,100,000)
Commitments to lend additional funds to customers with restructured loans	6,900,000
Foreclosed real estate	5,500,000	6,600,000
Personal property acquired in repossession	$ 2,400,000	$ 2,800,000