Loans - Consumer, Excluding Credit Card Loans, Impaired Loans (Details) (Consumer, excluding credit card, USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Home equity - senior lien
Impaired loans:
With an allowance	$ 553,000,000		$ 552,000,000
Without an allowance	534,000,000		549,000,000
Total impaired loans	1,087,000,000		1,101,000,000
Allowance for loan losses related to impaired loans	85,000,000		84,000,000
Unpaid principal balance of impaired loans	1,426,000,000		1,451,000,000
Average impaired loans	1,095,000,000	1,143,000,000
Interest income on impaired loans	13,000,000	14,000,000
Interest income on impaired loans on a cash basis	9,000,000	9,000,000
Home equity - senior lien | Permanent Modification | Regulatory Guidance Regarding Chapter 7 Loans
Impaired loans:
Rate of default for modified loans, estimated weighted average	18.00%
Home equity - senior lien | Nonaccrual
Impaired loans:
Total impaired loans	623,000,000		628,000,000
Home equity - junior lien
Impaired loans:
With an allowance	724,000,000		722,000,000
Without an allowance	569,000,000		582,000,000
Total impaired loans	1,293,000,000		1,304,000,000
Allowance for loan losses related to impaired loans	145,000,000		147,000,000
Unpaid principal balance of impaired loans	2,546,000,000		2,603,000,000
Average impaired loans	1,298,000,000	1,321,000,000
Interest income on impaired loans	20,000,000	21,000,000
Interest income on impaired loans on a cash basis	13,000,000	14,000,000
Home equity - junior lien | Permanent Modification | Regulatory Guidance Regarding Chapter 7 Loans
Impaired loans:
Rate of default for modified loans, estimated weighted average	11.00%
Home equity - junior lien | Nonaccrual
Impaired loans:
Total impaired loans	620,000,000		632,000,000
Mortgages - prime, including option ARMS
Impaired loans:
With an allowance	4,596,000,000		4,949,000,000
Without an allowance	1,142,000,000		1,196,000,000
Total impaired loans	5,738,000,000		6,145,000,000
Allowance for loan losses related to impaired loans	120,000,000		127,000,000
Unpaid principal balance of impaired loans	7,331,000,000		7,813,000,000
Average impaired loans	6,054,000,000	6,956,000,000
Interest income on impaired loans	59,000,000	68,000,000
Interest income on impaired loans on a cash basis	12,000,000	13,000,000
Mortgages - prime, including option ARMS | Permanent Modification | Regulatory Guidance Regarding Chapter 7 Loans
Impaired loans:
Rate of default for modified loans, estimated weighted average	23.00%
Mortgages - prime, including option ARMS | Nonaccrual
Impaired loans:
Total impaired loans	1,517,000,000		1,559,000,000
Mortgages - subprime
Impaired loans:
With an allowance	2,092,000,000		2,239,000,000
Without an allowance	613,000,000		639,000,000
Total impaired loans	2,705,000,000		2,878,000,000
Allowance for loan losses related to impaired loans	63,000,000		64,000,000
Unpaid principal balance of impaired loans	3,968,000,000		4,200,000,000
Average impaired loans	2,822,000,000	3,667,000,000
Interest income on impaired loans	37,000,000	49,000,000
Interest income on impaired loans on a cash basis	11,000,000	13,000,000
Mortgages - subprime | Permanent Modification | Regulatory Guidance Regarding Chapter 7 Loans
Impaired loans:
Rate of default for modified loans, estimated weighted average	15.00%
Mortgages - subprime | Nonaccrual
Impaired loans:
Total impaired loans	898,000,000		931,000,000
Residential real estate – excluding PCI
Impaired loans:
With an allowance	7,965,000,000		8,462,000,000
Without an allowance	2,858,000,000		2,966,000,000
Total impaired loans	10,823,000,000		11,428,000,000
Allowance for loan losses related to impaired loans	413,000,000		422,000,000
Unpaid principal balance of impaired loans	15,271,000,000		16,067,000,000
Loans modified subsequent to repurchase from Ginnie Mae	4,800,000,000		4,900,000,000
Average impaired loans	11,269,000,000	13,087,000,000
Interest income on impaired loans	129,000,000	152,000,000
Interest income on impaired loans on a cash basis	45,000,000	49,000,000
Number of payments under modified terms to recognize interest on cash basis	6
Residential real estate – excluding PCI | Current, and Less Than 90 Days Past Due
Impaired loans:
Period past due, credit analysis factors, charge off criteria	90 days
TDRs not having yet made six payments	2,800,000,000		2,900,000,000
Residential real estate – excluding PCI | Nonaccrual
Impaired loans:
Total impaired loans	$ 3,658,000,000		$ 3,750,000,000
Residential real estate – excluding PCI | Minimum | Days Past Due, 30 or More | Regulatory Guidance Regarding Chapter 7 Loans
Impaired loans:
Period past due, credit analysis factors, charge off criteria	30 days