Summary of the ALLL and Related Loans and Leases Classified by Portfolio Segment (Parenthetical) (Detail) (USD $) In Millions	Sep. 30, 2011		Jun. 30, 2011	Dec. 31, 2010		Sep. 30, 2010		Jun. 30, 2010	Dec. 31, 2009
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses	$ 2,439	[1]	$ 2,614	$ 3,004	[1]	$ 3,194	[1]	$ 3,693	$ 3,749
Portfolio loans and leases at fair value	62			46		42
Portfolio loans and leases	79,154	[2]		77,445	[3],[4]
Leveraged Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses	14			15
Portfolio loans and leases	1,018			1,039
Residential Mortgage Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Portfolio loans and leases at fair value	$ 62			$ 46

[1] Includes $35, $52, and $56 of cash, $7, $7 and $7 of other short-term investments, $29, $29 and $29 of commercial mortgage loans, $228, $241 and $248 of home equity loans, $334, $648 and $771 of automobile loans, ($10), ($14) and ($15) of ALLL, $3, $7 and $7 of other assets, $5, $12 and $17 of other liabilities and $270, $692 and $834 of long-term debt from consolidated VIEs that are included in their respective captions above at September 30, 2011, December 31, 2010 and September 30, 2010, respectively. See Note 9.

[2] Excludes $62 of loans measured at fair value.

[3] Excludes $46 of loans measured at fair value.

[4] Excludes $46 of residential mortgage loans measured at fair value, and includes $1,039 of leveraged leases, net of unearned income.