Condensed Balance Sheet - Parent Company Only (Detail) (USD $)	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Investments in subsidiaries:
Goodwill	$ 2,417,000,000		$ 2,417,000,000		$ 2,417,000,000
Other assets	8,863,000,000	[1]	8,400,000,000	[1]
Total Assets	116,967,000,000		111,007,000,000		113,380,000,000
Liabilities
Other short-term borrowings	3,239,000,000		1,574,000,000
Accrued expenses and other liabilities	3,270,000,000	[1]	2,979,000,000	[1]
Long-term debt	9,682,000,000	[1]	9,558,000,000	[1]
Total liabilities	103,716,000,000		96,927,000,000
Bancorp Shareholders' Equity	13,201,000,000		14,051,000,000
Parent Company [Member]
Assets
Cash	50,000,000		60,000,000
Short-term Investments	3,588,000,000		2,953,000,000
Loans to subsidiaries:
Bank subsidiaries			250,000,000
Nonbank subsidiaries	1,032,000,000		1,271,000,000
Total loans to subsidiaries	1,032,000,000		1,521,000,000
Investments in subsidiaries:
Nonbank subsidiaries	15,631,000,000		15,622,000,000
Total investment in subsidiaries	15,631,000,000		15,622,000,000
Goodwill	80,000,000		80,000,000
Other assets	731,000,000		545,000,000
Total Assets	21,112,000,000		20,781,000,000
Liabilities
Other short-term borrowings	655,000,000		414,000,000
Accrued expenses and other liabilities	422,000,000		356,000,000
Long-term debt	6,784,000,000		5,960,000,000
Total liabilities	7,861,000,000		6,730,000,000
Bancorp Shareholders' Equity	13,251,000,000		14,051,000,000
Total Liabilities and Bancorp Shareholders' Equity	$ 21,112,000,000		$ 20,781,000,000

[1] At December 31, 2011 and 2010, includes $30 and $52 of cash, $7 of other short-term investments, $50 and $29 of commercial mortgage loans, $223 and $241 of home equity loans, $259 and $648 of automobile loans, ($10) and ($14) of ALLL, $4 and $7 of other assets, $4 and $12 of other liabilities, $191 and $692 of long-term debt from consolidated VIEs that are included in their respective captions. See Note 11.