Guarantees, Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Guarantor Obligations [Line Items]
Operating Leases, Future Minimum Payments, Due in Three Years	$ 36,074
Operating Leases, Future Minimum Payments, Due in Four Years	31,043
Operating Leases, Future Minimum Payments, Due in Five Years	25,670
Operating Leases, Future Minimum Payments Due, Next Twelve Months	44,797
Operating Leases, Future Minimum Payments, Due Thereafter	94,049
Commitments to Extend Credit Expiring in One Year	5,900,000
standby letters of credit expiring in one year	568,000
Standby Letters of Credit, Thereafter	398,000
Guarantor Obligations, Current Carrying Value	4,700
Reserve for Unfunded Lending Commitments	1,600
Letters of Credit, Deferred Commitment Fees	3,100
Private Equity and other noninterest bearing investments [Table Text Block]	26,000
Commitments for Private Equity or Other Non-Interest Bearing Investments Prohibited by the Volcker Rule	4,000
Risk-weighted values assigned to all off-balance sheet financial and derivative instruments	6,500,000	$ 6,300,000
Cash Reserve Deposit Required and Made	353,600
Capital Lease Obligations, Current	1,200
Accumulated Amortization, Deferred Finance Costs	1,000
Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals	1,100
Future Minimum Sublease Rentals, Sale Leaseback Transactions, within Two Years	1,100
Future Minimum Sublease Rentals, Sale Leaseback Transactions, within Three Years	900
Operating Leases, Future Minimum Payments Receivable, in Four Years	100
Operating Leases, Rent Expense, Net	64,800	$ 62,500	$ 59,200
Minimum [Member]
Guarantor Obligations [Line Items]
Loss Contingency, Range of Possible Loss, Minimum	0
Maximum [Member]
Guarantor Obligations [Line Items]
Loss Contingency, Range of Possible Loss, Minimum	$ 20,000