Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Short-term debt and current maturities of long-term debt:
Total short-term debt and current maturities of long-term debt	$ 449	$ 384
Finance lease and other financing obligations	294	240
Long-term debt:
Unamortized discount and deferred financing costs	(131)	(155)
Finance lease and other financing obligations	581	504
Total long-term debt	20,540	20,300
Line of Credit \| Term loan facility
Long-term debt:
Long-term debt	355	1,250
Line of Credit \| Revolving credit facility
Long-term debt:
Long-term debt	$ 107	22
Senior Notes \| 4.750% senior notes due June 2021
Debt Instrument [Line Items]
Interest rate, stated percentage	4.75%
Long-term debt:
Long-term debt	$ 0	400
Senior Notes \| 3.500% senior notes due October 2022
Debt Instrument [Line Items]
Interest rate, stated percentage	3.50%
Long-term debt:
Long-term debt	$ 700	700
Senior Notes \| 0.375% senior notes due July 2023 (Euro-denominated)
Debt Instrument [Line Items]
Interest rate, stated percentage	0.375%
Long-term debt:
Long-term debt	$ 579	612
Senior Notes \| 3.800% senior notes due October 2023
Debt Instrument [Line Items]
Interest rate, stated percentage	3.80%
Long-term debt:
Long-term debt	$ 1,000	1,000
Senior Notes \| 2.750% senior notes due July 2024
Debt Instrument [Line Items]
Interest rate, stated percentage	2.75%
Long-term debt:
Long-term debt	$ 2,000	2,000
Senior Notes \| 3.850% senior notes due June 2025
Debt Instrument [Line Items]
Interest rate, stated percentage	3.85%
Long-term debt:
Long-term debt	$ 900	900
Senior Notes \| 2.250% senior notes due July 2025 (British Pound-denominated)
Debt Instrument [Line Items]
Interest rate, stated percentage	2.25%
Long-term debt:
Long-term debt	$ 707	709
Senior Notes \| 3.200% senior notes due July 2026
Debt Instrument [Line Items]
Interest rate, stated percentage	3.20%
Long-term debt:
Long-term debt	$ 2,000	2,000
Senior Notes \| 2.250% senior notes due June 2027
Debt Instrument [Line Items]
Interest rate, stated percentage	2.25%
Long-term debt:
Long-term debt	$ 1,000	1,000
Senior Notes \| 1.125% senior notes due July 2027 (Euro-denominated)
Debt Instrument [Line Items]
Interest rate, stated percentage	1.125%
Long-term debt:
Long-term debt	$ 579	612
Senior Notes \| 4.200% senior notes due October 2028
Debt Instrument [Line Items]
Interest rate, stated percentage	4.20%
Long-term debt:
Long-term debt	$ 1,000	1,000
Senior Notes \| 3.500% senior notes due July 2029
Debt Instrument [Line Items]
Interest rate, stated percentage	3.50%
Long-term debt:
Long-term debt	$ 3,000	3,000
Senior Notes \| 2.650% senior notes due June 2030
Debt Instrument [Line Items]
Interest rate, stated percentage	2.65%
Long-term debt:
Long-term debt	$ 1,000	1,000
Senior Notes \| 1.625% senior notes due July 2030 (Euro-denominated)
Debt Instrument [Line Items]
Interest rate, stated percentage	1.625%
Long-term debt:
Long-term debt	$ 579	612
Senior Notes \| 3.000% senior notes due July 2031 (British Pound-denominated)
Debt Instrument [Line Items]
Interest rate, stated percentage	3.00%
Long-term debt:
Long-term debt	$ 707	709
Senior Notes \| 4.400% senior notes due July 2049
Debt Instrument [Line Items]
Interest rate, stated percentage	4.40%
Long-term debt:
Long-term debt	$ 2,000	2,000
Receivable securitized loan
Long-term debt:
Long-term debt	500	425
U.S. commercial paper notes
Long-term debt:
Long-term debt	1,377	0
Foreign lines of credit
Short-term debt and current maturities of long-term debt:
Total short-term debt and current maturities of long-term debt	$ 155	$ 144

Finance Lease, Liability And Other, Current

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Finance Lease, Liability And Other, Noncurrent

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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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

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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 of unamortized debt discount (premium) and debt issuance costs.

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

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