Fair Value Fair Value (Schedule of Availability of Significant Unobservable Inputs by Balance Sheet Classification) (Details) (Fair Value, Inputs, Level 3 [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2012
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure	$ 6,931
Liabilities, Fair Value Disclosure	166
Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure	463	[1]
Liabilities, Fair Value Disclosure	166	[1]
Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure	6,468	[2]
Liabilities, Fair Value Disclosure	0	[2]
Mortgage Backed Securities [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	933
Mortgage Backed Securities [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	933	[2]
Asset-backed Securities, Student Loans [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	484
Asset-backed Securities, Student Loans [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	11	[1]
Asset-backed Securities, Student Loans [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	473	[2]
Asset-backed Securities, Credit Cards [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	274
Asset-backed Securities, Credit Cards [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	138	[1]
Asset-backed Securities, Credit Cards [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	136	[2]
Asset-backed Securities, Other [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	3,094
Asset-backed Securities, Other [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	104	[1]
Asset-backed Securities, Other [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	2,990	[2]
Non-US Debt Securities, Mortgage-Backed Securities [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	273
Non-US Debt Securities, Mortgage-Backed Securities [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[1]
Non-US Debt Securities, Mortgage-Backed Securities [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	273	[2]
Non-US Debt Securities, Asset-Backed Securities [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	1,362
Non-US Debt Securities, Asset-Backed Securities [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[1]
Non-US Debt Securities, Asset-Backed Securities [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	1,362	[2]
Non-US Debt Securities, Other [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	1
Non-US Debt Securities, Other [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	1	[1]
Non-US Debt Securities, Other [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[2]
US States and Political Subdivisions Debt Securities [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	49
US States and Political Subdivisions Debt Securities [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	49	[1]
US States and Political Subdivisions Debt Securities [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[2]
Collateralized Mortgage Obligations [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	301
Collateralized Mortgage Obligations [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[1]
Collateralized Mortgage Obligations [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Available-for-sale Securities, Fair Value Disclosure	301	[2]
Derivative Financial Instruments, Liabilities [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	157
Derivative Financial Instruments, Liabilities, Fair Value Disclosure	9
Derivative Financial Instruments, Liabilities [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	157	[1]
Derivative Financial Instruments, Liabilities, Fair Value Disclosure	9	[1]
Derivative Financial Instruments, Assets [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	160
Derivative Financial Instruments, Assets [Member] | Significant Unobservable Inputs Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	160	[1]
Derivative Financial Instruments, Assets [Member] | Significant Unobservable Inputs Not Readily Available [Member]
Fair Value, Measurements, Availability of Significant Unobservable Inputs [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	$ 0	[2]

[1] Information with respect to these model-priced financial assets and liabilities is provided in the preceding table.

[2] hese financial assets is measured using non-binding broker or dealer quotes.