Borrowings - Schedule of Borrowings (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Short-term debt	$ 255	$ 0
Finance lease obligations	919	808
Total debt principal	72,612	69,246
Debt premiums	256	262
Debt discounts and deferred financing costs	(1,050)	(1,028)
Long-term debt, short-term debt, and lease obligation	71,818	68,480
Short-term debt (commercial paper)	(255)	0
Current portion of long-term debt	(5,828)	(3,781)
Long-term debt	65,735	$ 64,699
Senior Notes \| 3.125% senior notes due March 2020
Debt Instrument [Line Items]
Debt interest rate		3.125%
Long-term debt	$ 0	$ 723
Senior Notes \| 2.8% senior notes due July 2020
Debt Instrument [Line Items]
Debt interest rate	2.80%
Long-term debt	$ 2,750	2,750
Senior Notes \| 3.35% senior notes due March 2021
Debt Instrument [Line Items]
Debt interest rate	3.35%
Long-term debt	$ 2,038	2,038
Senior Notes \| 4.125% senior notes due May 2021
Debt Instrument [Line Items]
Debt interest rate	4.125%
Long-term debt	$ 222	222
Senior Notes \| 2.125% senior notes due June 2021
Debt Instrument [Line Items]
Debt interest rate	2.125%
Long-term debt	$ 1,750	1,750
Senior Notes \| 4.125% senior notes due June 2021
Debt Instrument [Line Items]
Debt interest rate	4.125%
Long-term debt	$ 203	203
Senior Notes \| 5.45% senior notes due June 2021
Debt Instrument [Line Items]
Debt interest rate	5.45%
Long-term debt	$ 187	187
Senior Notes \| 3.5% senior notes due July 2022
Debt Instrument [Line Items]
Debt interest rate	3.50%
Long-term debt	$ 1,500	1,500
Senior Notes \| 2.75% senior notes due November 2022
Debt Instrument [Line Items]
Debt interest rate	2.75%
Long-term debt	$ 1,000	1,000
Senior Notes \| 2.75% senior notes due December 2022
Debt Instrument [Line Items]
Debt interest rate	2.75%
Long-term debt	$ 1,250	1,250
Senior Notes \| 4.75% senior notes due December 2022
Debt Instrument [Line Items]
Debt interest rate	4.75%
Long-term debt	$ 399	399
Senior Notes \| 3.7% senior notes due March 2023
Debt Instrument [Line Items]
Debt interest rate	3.70%
Long-term debt	$ 6,000	6,000
Senior Notes \| 2.8% senior notes due June 2023
Debt Instrument [Line Items]
Debt interest rate	2.80%
Long-term debt	$ 1,300	1,300
Senior Notes \| 4% senior notes due December 2023
Debt Instrument [Line Items]
Debt interest rate	4.00%
Long-term debt	$ 1,250	1,250
Senior Notes \| 2.625% senior notes due August 2024
Debt Instrument [Line Items]
Debt interest rate	2.265%
Long-term debt	$ 1,000	1,000
Senior Notes \| 3.375% senior notes due August 2024
Debt Instrument [Line Items]
Debt interest rate	3.375%
Long-term debt	$ 650	650
Senior Notes \| 3.5% senior notes due November 2024
Debt Instrument [Line Items]
Debt interest rate	3.50%
Long-term debt	$ 750	750
Senior Notes \| 5% senior notes due December 2024
Debt Instrument [Line Items]
Debt interest rate	5.00%
Long-term debt	$ 299	299
Senior Notes \| 4.1% senior notes due March 2025
Debt Instrument [Line Items]
Debt interest rate	4.10%
Long-term debt	$ 5,000	5,000
Senior Notes \| 3.875% senior notes due July 2025
Debt Instrument [Line Items]
Debt interest rate	3.875%
Long-term debt	$ 2,828	2,828
Senior Notes \| 2.875% senior notes due June 2026
Debt Instrument [Line Items]
Debt interest rate	2.875%
Long-term debt	$ 1,750	1,750
Senior Notes \| 3% senior notes due August 2026
Debt Instrument [Line Items]
Debt interest rate	3.00%
Long-term debt	$ 750	750
Senior Notes \| 3.625% senior notes due April 2027
Debt Instrument [Line Items]
Debt interest rate	3.625%
Long-term debt	$ 750	0
Senior Notes \| 6.25% senior notes due June 2027
Debt Instrument [Line Items]
Debt interest rate	6.25%
Long-term debt	$ 372	372
Senior Notes \| 4.3% senior notes due March 2028
Debt Instrument [Line Items]
Debt interest rate	4.30%
Long-term debt	$ 9,000	9,000
Senior Notes \| 3.25% senior notes due August 2029
Debt Instrument [Line Items]
Debt interest rate	3.25%
Long-term debt	$ 1,750	1,750
Senior Notes \| 3.75% senior notes due April 2030
Debt Instrument [Line Items]
Debt interest rate	3.75%
Long-term debt	$ 1,500	0
Senior Notes \| 4.875% senior notes due July 2035
Debt Instrument [Line Items]
Debt interest rate	4.875%
Long-term debt	$ 652	652
Senior Notes \| 6.625% senior notes due June 2036
Debt Instrument [Line Items]
Debt interest rate	6.625%
Long-term debt	$ 771	771
Senior Notes \| 6.75% senior notes due December 2037
Debt Instrument [Line Items]
Debt interest rate	6.75%
Long-term debt	$ 533	533
Senior Notes \| 4.78% senior notes due March 2038
Debt Instrument [Line Items]
Debt interest rate	4.78%
Long-term debt	$ 5,000	5,000
Senior Notes \| 6.125% senior notes due September 2039
Debt Instrument [Line Items]
Debt interest rate	6.125%
Long-term debt	$ 447	447
Senior Notes \| 4.125% senior notes due April 2040
Debt Instrument [Line Items]
Debt interest rate	4.125%
Long-term debt	$ 1,000	0
Senior Notes \| 5.75% senior notes due May 2041
Debt Instrument [Line Items]
Debt interest rate	5.75%
Long-term debt	$ 133	133
Senior Notes \| 4.5% senior notes due May 2042
Debt Instrument [Line Items]
Debt interest rate	4.50%
Long-term debt	$ 500	500
Senior Notes \| 4.125% senior notes due November 2042
Debt Instrument [Line Items]
Debt interest rate	4.125%
Long-term debt	$ 500	500
Senior Notes \| 5.3% senior notes due December 2043
Debt Instrument [Line Items]
Debt interest rate	5.30%
Long-term debt	$ 750	750
Senior Notes \| 4.75% senior notes due March 2044
Debt Instrument [Line Items]
Debt interest rate	4.75%
Long-term debt	$ 375	375
Senior Notes \| 5.125% senior notes due July 2045
Debt Instrument [Line Items]
Debt interest rate	5.125%
Long-term debt	$ 3,500	3,500
Senior Notes \| 3.875% senior notes due August 2047
Debt Instrument [Line Items]
Debt interest rate	3.875%
Long-term debt	$ 1,000	1,000
Senior Notes \| 5.05% senior notes due March 2048
Debt Instrument [Line Items]
Debt interest rate	5.05%
Long-term debt	$ 8,000	8,000
Senior Notes \| 4.25% senior notes due April 2050
Debt Instrument [Line Items]
Debt interest rate	4.25%
Long-term debt	$ 750	$ 0
Floating Rate Notes \| Floating rate notes due March 2020 (2.515% at December 31, 2019)
Debt Instrument [Line Items]
Debt interest rate		2.515%
Long-term debt	$ 0	$ 277
Floating Rate Notes \| Floating rate notes due March 2021 (1.719% at March 31, 2020 and 2.605% at December 31, 2019)
Debt Instrument [Line Items]
Debt interest rate	1.719%	2.605%
Long-term debt	$ 1,000	$ 1,000
Other Debt Obligations
Debt Instrument [Line Items]
Long-term debt	$ 279	$ 279

Debt Instrument, Unamortized Discount and Debt Issuance Costs, Net

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- Definition

Debt, Long-Term And Short-Term And Lease Obligation, Combined Amount, Gross

+ References

No definition available.

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Debt, Long-Term And Short-Term And Lease Obligation, Combined Amount, Net

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- Definition

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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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt premium.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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