Reclassifications Out of Accumulated Other Comprehensive Income (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Reclassifications Out Of Accumulated Other Comprehensive Income
Income Before Income Taxes	$ 438		$ 591
Applicable income tax expense	119		179
Net income	318		422
Net Unrealized Gains On Available For Sale Securities | Net Losses Included In Net Income
Reclassifications Out Of Accumulated Other Comprehensive Income
Reclassification adjustment for net losses (gains) included in net income	5	[1]	(7)	[1]
Income Before Income Taxes	5	[1]	(7)	[1]
Applicable income tax expense	(2)	[1]	2	[1]
Net income	3	[1]	(5)	[1]
Net Unrealized Gains On Cash Flow Hedge Activities
Reclassifications Out Of Accumulated Other Comprehensive Income
Income Before Income Taxes	10	[1]	21	[1]
Applicable income tax expense	(3)	[1]	(7)	[1]
Net income	7	[1]	14	[1]
Net Unrealized Gains On Cash Flow Hedge Activities | Interest Rate Contracts Related To C&I Loans
Reclassifications Out Of Accumulated Other Comprehensive Income
Reclassification adjustment for net gains on cash flow hedge derivatives included in net income	10	[1]	22	[1]
Net Unrealized Gains On Cash Flow Hedge Activities | Interest Rate Contracts Related To Long-Term Debt
Reclassifications Out Of Accumulated Other Comprehensive Income
Reclassification adjustment for net gains on cash flow hedge derivatives included in net income			(1)	[1]
Amortization Of Defined Benefit Pension Items | Net Actuarial Loss
Reclassifications Out Of Accumulated Other Comprehensive Income
Net periodic pension cost	(2)	[1],[2]	(3)	[1],[2]
Income Before Income Taxes	(2)	[1]	(3)	[1]
Applicable income tax expense	1	[1]	1	[1]
Net income	(1)	[1]	(2)	[1]
Total Reclassifications For The Period
Reclassifications Out Of Accumulated Other Comprehensive Income
Net income	$ 9	[1]	$ 7	[1]

[1] Amounts in parentheses indicate reductions to net income

[2] This AOCI component is included in the computation of net periodic benefit cost. Refer to Note 21 in the Bancorp’s Annual Report on Form 10-K for the year ended December 31, 2013 for information on the computation of net periodic benefit cost.