Debt and Other Obligations Contractual Maturities (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Contractual Maturities [Abstract]
Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year	$ 28
Long-term Debt, Maturities, Repayments of Principal in Year Two	99
Long-term Debt, Maturities, Repayments of Principal in Year Three	1,674
Long-term Debt, Maturities, Repayments of Principal in Year Four	998
Long-term Debt, Maturities, Repayments of Principal in Year Five	3,603
Long-term Debt, Maturities, Repayments of Principal after Year Five	11,566
Total Cash Obligations	17,968
Unamortized Adjustments, Net	(118)
Debt and Finance Lease Obligations	$ 17,850	$ 16,682

Contractual Maturities [Abstract]

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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.

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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 fourth 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 third 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 second 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 remainder of the 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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