Fair Value Measurements (Non-Recurring Measurement) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Financing receivables and loans held for sale [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Weighted Average Capitalization Rate Used For Level Three Valuation	8.20%
Financing receivables and loans held for sale [Member] | Lower Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Capitalization Rate Used For Level Three Valuation	6.70%
Financing receivables and loans held for sale [Member] | Upper Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Capitalization Rate Used For Level Three Valuation	12.80%
Cost and equity method investments [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Weighted Average Capitalization Rate Used For Level Three Valuation	8.60%
Cost and equity method investments [Member] | Lower Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Capitalization Rate Used For Level Three Valuation	8.60%
Cost and equity method investments [Member] | Upper Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Capitalization Rate Used For Level Three Valuation	8.60%
Long Lived Assets, Including Real Estate [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Weighted Average Capitalization Rate Used For Level Three Valuation	6.20%
Long Lived Assets, Including Real Estate [Member] | Lower Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Capitalization Rate Used For Level Three Valuation	4.80%
Long Lived Assets, Including Real Estate [Member] | Upper Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Capitalization Rate Used For Level Three Valuation	10.60%
Domestic Corporate Debt Securities [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Weighted Average Discount Rate Used For Level Three Valuation	10.30%
Domestic Corporate Debt Securities [Member] | Lower Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Discount Rate Used For Level Three Valuation	2.00%
Domestic Corporate Debt Securities [Member] | Upper Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Discount Rate Used For Level Three Valuation	20.90%
Asset-backed Securities [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Weighted Average Discount Rate Used For Level Three Valuation	4.40%
Asset-backed Securities [Member] | Lower Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Discount Rate Used For Level Three Valuation	1.90%
Asset-backed Securities [Member] | Upper Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Discount Rate Used For Level Three Valuation	18.00%
Foreign Corporate Debt Securities [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Weighted Average Discount Rate Used For Level Three Valuation	9.90%
Foreign Corporate Debt Securities [Member] | Lower Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Discount Rate Used For Level Three Valuation	2.30%
Foreign Corporate Debt Securities [Member] | Upper Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Discount Rate Used For Level Three Valuation	27.20%
Other [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Weighted Average Cost Of Capital Used For Level Three Valuation	8.80%
Other [Member] | Lower Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Cost Of Capital Used For Level Three Valuation	8.80%
Other [Member] | Upper Limit [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Range Cost Of Capital Used For Level Three Valuation	11.50%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Domestic Corporate Debt Securities [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Investments, Fair Value Disclosure	1,539
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Asset-backed Securities [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Investments, Fair Value Disclosure	4,358
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Foreign Corporate Debt Securities [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Investments, Fair Value Disclosure	713
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Other [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Investments, Fair Value Disclosure	381
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Financing receivables and loans held for sale [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Investments, Fair Value Disclosure	1,221
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Cost and equity method investments [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Investments, Fair Value Disclosure	28
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Long Lived Assets, Including Real Estate [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]
Investments, Fair Value Disclosure	200