Fair Value, Option, Carrying Amount (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgages held for sale	$ 25,175	$ 47,531
Mortgages held for sale, Unpaid principal	25,174	47,818
Loans held for sale	1,102	873
Loans held for sale, Unpaid principal	1,123	897
Loans	0	309
Loans, Unpaid principal	0	348
Long-term debt	0	306
Long-term debt, Unpaid principal	0	353
Long-term debt, Aggregate differences	0	(47)
Mortgages held for sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loan held for sale, aggregate difference	1	(287)
Nonaccrual loans	261	325
Nonaccrual loans, Unpaid principal	549	662
Nonaccrual loans, Aggregate difference	(288)	(337)
Loans 90 days or more past due and still accruing	32	38
Loans 90 days or more past due and still accruing, Unpaid principal	41	47
Loans 90 days or more past due and still accruing, Aggregate difference	(9)	(9)
Loans held for sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loan held for sale, aggregate difference	(21)	(24)
Nonaccrual loans	16	1
Nonaccrual loans, Unpaid principal	22	7
Nonaccrual loans, Aggregate difference	(6)	(6)
Loans [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loan held for sale, aggregate difference	0	(39)
Nonaccrual loans	0	13
Nonaccrual loans, Unpaid principal	0	16
Nonaccrual loans, Aggregate difference	0	(3)
Loans 90 days or more past due and still accruing	0	2
Loans 90 days or more past due and still accruing, Unpaid principal	0	2
Loans 90 days or more past due and still accruing, Aggregate difference	$ 0	$ 0