Certain Employee Benefit and Stock-Based Compensation Plans (Summary of Stock Option Activity) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock options, beginning balance	18,439
Stock options granted during the period	461
Stock options exercised during the period	(2,383)
Stock options cancelled during the period	(796)
Outstanding stock options, ending balance	15,721
Weighted-average exercise price, beginning of period	$ 86.90
Weighted-average exercise price of shares granted during period	$ 60.70
Weighted-average exercise price of shares exercised during period	$ 47.67
Weighted-average exercise price of shares cancelled during period	$ 219
Weighted-average exercise price, end of period	$ 85.42
Shares exercisable at end of period	12,856
Weighted average exercisable price of shares exercisable at end of period	$ 90.81
Employee Stock Option Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock options, beginning balance	17,490
Stock options granted during the period	461
Stock options exercised during the period	(2,383)
Stock options cancelled during the period	(604)
Outstanding stock options, ending balance	14,964
Weighted-average exercise price, beginning of period	$ 54.48
Weighted-average exercise price of shares granted during period	$ 60.70
Weighted-average exercise price of shares exercised during period	$ 47.67
Weighted-average exercise price of shares cancelled during period	$ 62.37
Weighted-average exercise price, end of period	$ 55.44
Shares exercisable at end of period	12,099
Weighted average exercisable price of shares exercisable at end of period	$ 54.07
Stock Options Converted From National City Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock options, beginning balance	949
Stock options cancelled during the period	(192)
Outstanding stock options, ending balance	757
Weighted-average exercise price, beginning of period	$ 684
Weighted-average exercise price of shares cancelled during period	$ 712
Weighted-average exercise price, end of period	$ 678
Shares exercisable at end of period	757
Weighted average exercisable price of shares exercisable at end of period	$ 678