Summary Of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2011 months days years
Summary Of Significant Accounting Policies [Abstract]
Subsidiary locations	360
Fixed rate intervals, years or more	3
Amortization period of credit card loans, months	12
Period past due loans are placed on non-accrual, days	90
Consumer loans charged down to fair value, days delinquent	120
Receivable past due, days	180
Long-term agreements to resell	$ 850,000,000
Securities sold under agreements to repurchase	702,800,000
Securities accepted as collateral	894,400,000
Long-term structured repurchase agreements	400,000,000
Available for sale securities as collateral for repurchase agreements	$ 2,000,000,000
Depreciable lives for buildings, years	30
Depreciable lives for building improvements, years	10
Minimum depreciable lives for equipment, years	3
Maximum depreciable lives for equipment, years	8
Core deposit intangibles amortized over years, minimum	8
Core deposit intangibles amortized over years, maximum	14
Interest rate swaps designated as fair value hedges	3
Common stock dividend rate percentage	5.00%