Debt (Annual Debt Marturities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Long-term Debt, Fiscal Year Maturity [Abstract]
2017	$ 1,269
2018	347
2019	230
2020	198
2021	2,030
Thereafter	7,771
Total debt, gross	11,845
Debt Issuance Costs, Net	114
Less: Discount	25
Debt and Lease Obligation	$ 11,706	$ 10,785

Amount of short-term and long-term debt and lease obligation.

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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, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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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 in the next 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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