Debt (Annual Debt Marturities) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Long-term Debt, Fiscal Year Maturity [Abstract]
2017	$ 642
2018	246
2019	259
2020	1,019
2021	2,535
Thereafter	6,217
Total debt, gross	10,918
Debt Issuance Costs, Net	112
Less: Discount	21
Debt and Capital Lease Obligations	$ 10,785	$ 11,405

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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