Fair Value Fair Value (Fair Value Inputs, Assets and Liabilities, Quantitative Information) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Sep. 30, 2012
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Assumptions, Expected Term	10 years 9 months 21 days
Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	6,518
Liabilities, Fair Value Disclosure	109
Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities, Student Loans [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	478
Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities, Credit Cards [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	238
Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities, Other [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	3,460
Fair Value, Inputs, Level 3 [Member] | Non-US Debt Securities, Other [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	194
Fair Value, Inputs, Level 3 [Member] | US States and Political Subdivisions Debt Securities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	48
Fair Value, Inputs, Level 3 [Member] | Other U.S. Debt Securities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	9
Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	100
Derivative Financial Instruments, Liabilities, Fair Value Disclosure	9
Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Asset-backed Securities, Student Loans [Member] | Weighted Average [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Credit Spread Risk	6.70%
Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Asset-backed Securities, Credit Cards [Member] | Weighted Average [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Credit Spread Risk	3.00%
Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Asset-backed Securities, Other [Member] | Weighted Average [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Credit Spread Risk	2.00%
Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | US States and Political Subdivisions Debt Securities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Credit Spread Risk	1.90%
Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Derivative Financial Instruments, Liabilities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Inputs, Participant Redemptions	5.90%
Fair Value, Inputs, Level 3 [Member] | Option Model Approach Valuation Technique [Member] | Derivative Financial Instruments, Liabilities [Member] | Weighted Average [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Assumptions, Expected Volatility Rate	9.30%
Derivative Financial Instruments, Assets [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	99
Derivative Financial Instruments, Assets [Member] | Fair Value, Inputs, Level 3 [Member] | Option Model Approach Valuation Technique [Member] | Weighted Average [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Fair Value Assumptions, Expected Volatility Rate	9.30%
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	398	[1]
Liabilities, Fair Value Disclosure	109	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities, Student Loans [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	12	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities, Credit Cards [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	138	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed Securities, Other [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	101	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Non-US Debt Securities, Other [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | US States and Political Subdivisions Debt Securities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	48	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Other U.S. Debt Securities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	100	[1]
Derivative Financial Instruments, Liabilities, Fair Value Disclosure	9	[1]
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Asset-backed Securities, Student Loans [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	12
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Asset-backed Securities, Credit Cards [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	138
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Asset-backed Securities, Other [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	101
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | US States and Political Subdivisions Debt Securities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Available-for-sale Securities, Fair Value Disclosure	48
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Income Approach Valuation Technique [Member] | Derivative Financial Instruments, Liabilities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Derivative Financial Instruments, Liabilities, Fair Value Disclosure	9
Significant Unobservable Inputs Readily Available [Member] | Fair Value, Inputs, Level 3 [Member] | Option Model Approach Valuation Technique [Member] | Derivative Financial Instruments, Liabilities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	100
Significant Unobservable Inputs Readily Available [Member] | Derivative Financial Instruments, Assets [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	99	[1]
Significant Unobservable Inputs Readily Available [Member] | Derivative Financial Instruments, Assets [Member] | Fair Value, Inputs, Level 3 [Member] | Option Model Approach Valuation Technique [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	99

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