Fair Value Measurements (Details 5) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Assets:
Mortgage servicing rights	$ 1,508	$ 1,442	$ 1,236	$ 1,413
Debt:
Fair value of debt	5,900	8,200
Forward delivery commitments [Member] | Fair Value, Measurements, Recurring [Member] | Level Two [Member]
Other assets:
Other assets, fair value disclosure	43	309
Other liabilities:
Other liabilities, fair value disclosure	52	82
Interest rate contracts [Member] | Fair Value, Measurements, Recurring [Member] | Level Two [Member]
Other assets:
Other assets, fair value disclosure	2	4
Foreign Exchange Contract [Member] | Fair Value, Measurements, Recurring [Member] | Level Two [Member]
Other liabilities:
Other liabilities, fair value disclosure	1
Fair Value, Measurements, Recurring [Member] | Level Two [Member]
Assets:
Restricted investments	241	254
Mortgage loans held for sale	1,552	4,157
Fair Value, Measurements, Recurring [Member] | Level Two [Member] | Option Contracts [Member]
Other assets:
Other assets, fair value disclosure	3
Interest rate lock commitments [Member] | Fair Value, Measurements, Recurring [Member] | Level Three [Member]
Other assets:
Other assets, fair value disclosure	52	42
Other liabilities:
Other liabilities, fair value disclosure	4	46
Convertible note-related agreements [Member] | Fair Value, Measurements, Recurring [Member] | Level Three [Member]
Other assets:
Other assets, fair value disclosure	31	54
Other liabilities:
Other liabilities, fair value disclosure	31	54
Fair Value, Measurements, Recurring [Member] | Level Three [Member]
Assets:
Mortgage loans held for sale	155	172
Mortgage servicing rights	1,508	1,442
Fair Value, Measurements, Recurring [Member] | Level Three [Member] | Securitized mortgage loans [Member]
Other assets:
Other assets, fair value disclosure	34	42
Fair Value, Measurements, Recurring [Member] | Level Three [Member] | Mortgage loan securitization debt certificates [Member]
Debt:
Fair value of debt	26	30
Forward delivery commitments [Member] | Fair Value, Measurements, Recurring [Member] | Cash Collateral and Netting [Member]
Other assets:
Other assets, fair value disclosure	(23)	(241)
Other liabilities:
Other liabilities, fair value disclosure	(33)	(51)
Interest rate lock commitments [Member] | Fair Value, Measurements, Recurring [Member]
Other assets:
Other assets, fair value disclosure	52	42
Other liabilities:
Other liabilities, fair value disclosure	4	46
Forward delivery commitments [Member] | Fair Value, Measurements, Recurring [Member]
Other assets:
Other assets, fair value disclosure	20	68
Other liabilities:
Other liabilities, fair value disclosure	19	31
Interest rate contracts [Member] | Fair Value, Measurements, Recurring [Member]
Other assets:
Other assets, fair value disclosure	2	4
Convertible note-related agreements [Member] | Fair Value, Measurements, Recurring [Member]
Other assets:
Other assets, fair value disclosure	31	54
Other liabilities:
Other liabilities, fair value disclosure	31	54
Foreign Exchange Contract [Member] | Fair Value, Measurements, Recurring [Member]
Other liabilities:
Other liabilities, fair value disclosure	1
Fair Value, Measurements, Recurring [Member]
Assets:
Restricted investments	241	254
Mortgage loans held for sale	1,707	4,329
Mortgage servicing rights	1,508	1,442
Fair Value, Measurements, Recurring [Member] | Securitized mortgage loans [Member]
Other assets:
Other assets, fair value disclosure	34	42
Fair Value, Measurements, Recurring [Member] | Option Contracts [Member]
Other assets:
Other assets, fair value disclosure	3
Fair Value, Measurements, Recurring [Member] | Mortgage loan securitization debt certificates [Member]
Debt:
Fair value of debt	$ 26	$ 30