Debt and Credit Facilities - Summary of Debt Carrying Amount (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total debt, net	$ 29,290	$ 24,593
Less: current portion	1,498	2,499
Total long-term debt, net	$ 27,792	22,094
Senior Notes \| 2.35% Senior Unsecured Notes Due February 2020
Debt Instrument [Line Items]
Interest rate, stated percentage	2.35%
Long-term debt	$ 0	500
Senior Notes \| 2.55% Senior Unsecured Notes Due September 2020
Debt Instrument [Line Items]
Interest rate, stated percentage	2.55%
Long-term debt	$ 0	1,999
Senior Notes \| 4.50% Senior Unsecured Notes Due April 2021
Debt Instrument [Line Items]
Interest rate, stated percentage	4.50%
Long-term debt	$ 999	998
Senior Notes \| 0.15% LIBOR Senior Unsecured Notes Due September 2021
Debt Instrument [Line Items]
Long-term debt	$ 499	0
Senior Notes \| 0.15% LIBOR Senior Unsecured Notes Due September 2021 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	0.15%
Senior Notes \| 4.40% Senior Unsecured Notes Due December 2021
Debt Instrument [Line Items]
Interest rate, stated percentage	4.40%
Long-term debt	$ 1,249	1,248
Senior Notes \| 1.95% Senior Unsecured Notes Due March 2022
Debt Instrument [Line Items]
Interest rate, stated percentage	1.95%
Long-term debt	$ 499	499
Senior Notes \| 3.25% Senior Unsecured Notes Due September 2022
Debt Instrument [Line Items]
Interest rate, stated percentage	3.25%
Long-term debt	$ 998	998
Senior Notes \| 2.50% Senior Unsecured Notes Due September 2023
Debt Instrument [Line Items]
Interest rate, stated percentage	2.50%
Long-term debt	$ 747	747
Senior Notes \| 0.52% LIBOR Senior Unsecured Notes Due September 2023
Debt Instrument [Line Items]
Long-term debt	$ 496	0
Senior Notes \| 0.52% LIBOR Senior Unsecured Notes Due September 2023 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	0.52%
Senior Notes \| 0.75% Senior Unsecured Notes Due September 2023
Debt Instrument [Line Items]
Interest rate, stated percentage	0.75%
Long-term debt	$ 1,992	0
Senior Notes \| 3.70% Senior Unsecured Notes Due April 2024
Debt Instrument [Line Items]
Interest rate, stated percentage	3.70%
Long-term debt	$ 1,746	1,745
Senior Notes \| 3.50% Senior Unsecured Notes Due February 2025
Debt Instrument [Line Items]
Interest rate, stated percentage	3.50%
Long-term debt	$ 1,746	1,746
Senior Notes \| 3.65% Senior Unsecured Notes Due March 2026
Debt Instrument [Line Items]
Interest rate, stated percentage	3.65%
Long-term debt	$ 2,736	2,734
Senior Notes \| 2.95% Senior Unsecured Notes Due March 2027
Debt Instrument [Line Items]
Interest rate, stated percentage	2.95%
Long-term debt	$ 1,246	1,245
Senior Notes \| 1.20% Senior Unsecured Notes Due October 2027
Debt Instrument [Line Items]
Interest rate, stated percentage	1.20%
Long-term debt	$ 745	0
Senior Notes \| 1.65% Senior Unsecured Notes Due October 2030
Debt Instrument [Line Items]
Interest rate, stated percentage	1.65%
Long-term debt	$ 992	0
Senior Notes \| 4.60% Senior Unsecured Notes Due September 2035
Debt Instrument [Line Items]
Interest rate, stated percentage	4.60%
Long-term debt	$ 991	991
Senior Notes \| 4.00% Senior Unsecured Notes Due September 2036
Debt Instrument [Line Items]
Interest rate, stated percentage	4.00%
Long-term debt	$ 741	741
Senior Notes \| 2.60% Senior Unsecured Notes Due October 2040
Debt Instrument [Line Items]
Interest rate, stated percentage	2.60%
Long-term debt	$ 986	0
Senior Notes \| 5.65% Senior Unsecured Notes Due December 204
Debt Instrument [Line Items]
Interest rate, stated percentage	5.65%
Long-term debt	$ 996	995
Senior Notes \| 4.80% Senior Unsecured Notes Due April 2044
Debt Instrument [Line Items]
Interest rate, stated percentage	4.80%
Long-term debt	$ 1,735	1,734
Senior Notes \| 4.50% Senior Unsecured Notes Due February 2045
Debt Instrument [Line Items]
Interest rate, stated percentage	4.50%
Long-term debt	$ 1,732	1,731
Senior Notes \| 4.75% Senior Unsecured Notes Due March 2046
Debt Instrument [Line Items]
Interest rate, stated percentage	4.75%
Long-term debt	$ 2,218	2,217
Senior Notes \| 4.15% Senior Unsecured Notes Due March 2047
Debt Instrument [Line Items]
Interest rate, stated percentage	4.15%
Long-term debt	$ 1,726	1,725
Senior Notes \| 2.80% Senior Unsecured Notes Due October 2050
Debt Instrument [Line Items]
Interest rate, stated percentage	2.80%
Long-term debt	$ 1,475	$ 0

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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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.

+ References

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- Definition

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.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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