v3.3.0.814

Debt (Fair Value of Debt) (Details) - USD ($) $ in Millions | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | $ 11,157 | $ 11,122
Unsecured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,450 | 2,800
Loans Payable [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 2,780 | 2,799
Corporate Debt Securities [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 1,928 | 2,075
Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 11,356 | 10,958
Reported Value Measurement [Member] | Unsecured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,450 | 2,800
Reported Value Measurement [Member] | Loans Payable [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 2,780 | 2,799
Reported Value Measurement [Member] | Corporate Debt Securities [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 1,928 | 2,075
Reported Value Measurement [Member] | Notes Payable, Other Payable excluding Capital Leases [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt | [1] | 1,613 | 1,688
Reported Value Measurement [Member] | Secured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 1,585 | 1,596
Fair Value, Inputs, Level 2 [Member] | Unsecured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,188 | 2,832
Fair Value, Inputs, Level 2 [Member] | Loans Payable [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 2,755 | 2,769
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 2,023 | 2,247
Fair Value, Inputs, Level 2 [Member] | Secured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 1,548 | 1,540
Fair Value, Inputs, Level 3 [Member] | Notes Payable, Other Payable excluding Capital Leases [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt | [1] | $ 1,643 | $ 1,734
[1] | Excludes a lease that is accounted for as a failed sale-leaseback transaction under U.S. GAAP.

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