v3.19.2

Debt (Debt) (Details) - USD ($) $ in Millions | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | $ 10,724 | $ 10,785
Debt, Current | 263 | 637
Long-term Debt, Excluding Current Maturities | 10,461 | 10,148
Unsecured Debt [Member] |  |
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | 2,990 | 3,036
Loans Payable [Member] |  |
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | 2,979 | 2,976
Corporate Debt Securities [Member] |  |
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | 2,402 | 2,400
Notes Payable, Other Payables [Member] |  |
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | 1,229 | 1,264
Secured Debt [Member] |  |
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | 971 | 974
Capital Lease Obligations [Member] |  |
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | 78 | 105
Revolving Credit Facility [Member] |  |
Debt Instrument [Line Items] |  |
Debt and Lease Obligation | $ 75 | $ 30

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