v3.19.3.a.u2

Debt (Fair Value of Debt) (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | $ 11,857 | $ 10,156
Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 11,571 | 10,604
Unsecured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,663 | 3,036
Unsecured Debt [Member] | Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,663 | 3,036
Loans Payable [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,167 | 2,976
Loans Payable [Member] | Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,167 | 2,976
Corporate Debt Securities [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 2,835 | 2,400
Corporate Debt Securities [Member] | Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 2,835 | 2,400
Notes Payable, Other Payable excluding Capital Leases [Member] | Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt | [1] | 817 | 1,188
Secured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 967 | 974
Secured Debt [Member] | Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 967 | 974
Revolving Credit Facility [Member] | Reported Value Measurement [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 122 | 30
Fair Value, Inputs, Level 2 [Member] | Unsecured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,764 | 2,803
Fair Value, Inputs, Level 2 [Member] | Loans Payable [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 3,238 | 2,877
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 2,929 | 2,299
Fair Value, Inputs, Level 2 [Member] | Secured Debt [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | 982 | 938
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] | 822 | 1,209
Fair Value, Inputs, Level 3 [Member] | Revolving Credit Facility [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Long-term Debt |  | $ 122 | $ 30
[1] | Excludes a lease that is accounted for as a failed sale-leaseback transaction under U.S. GAAP.

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