Calculation of Earnings Per Share and the Reconciliation of Earnings Per Share to Earnings Per Diluted Share (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Earnings per share:
Net income attributable to Bancorp	$ 1,297	$ 753	$ 737
Dividends on preferred stock	203	250	226
Net income (loss) available to common shareholders	1,094	503	511
Less: Income allocated to participating securities	(6)	(3)	(4)
Net income allocated to common shareholders	1,088	500	507
Earnings per diluted share:
Net income available to common shareholders	1,094	503	511
Series G convertible preferred stock	35		(21)	[1]
Net income available to common shareholders plus assumed conversions	1,129	503	490
Less: Income allocated to participating securities	(6)	(3)	(4)
Net income allocated to common shareholders plus assumed conversions	$ 1,123	$ 500	$ 486
Earnings per share:
Net income allocated to common shareholders	906	791	696
Effect of dilutive securities:
Stock-based awards	6	5	2
Series G convertible preferred stock	36		28	[1]
Warrant related to Series F preferred stock	2	3
Net income allocated to common shareholders plus assumed conversions	950	799	726
Earnings per share:
Net income allocated to common shareholders	$ 1.20	$ 0.63	$ 0.73
Effect of dilutive securities:
Series G convertible preferred stock	$ (0.02)		$ (0.06)	[1]
Net income allocated to common shareholders plus assumed conversions	$ 1.18	$ 0.63	$ 0.67

[1] The additive effect to income from dividends on convertible preferred stock for the year ended December 31, 2009 included preferred dividends of $14 for Series G preferred shares, offset by a $35 reduction to preferred dividends due to the conversion of a portion of Series G preferred shares during the second quarter of 2009.