Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
Total borrowings at face value	$ 37,401	$ 37,401
Unamortized premium, net	892	914
Debt issuance costs	(117)	(125)
Long-term finance leases	308	347
Finance lease liabilities, current	38	51
Long-term Debt, Total	38,522	38,588
Less current maturities of long-term debt	(2,464)	(51)
Long-term Debt, Excluding Current Maturities	$ 36,058	$ 38,537

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Face (par) amount of debt instrument at time of issuance.

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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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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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