Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt, gross	$ 14,014	$ 12,775
Less: Unamortized discount and debt issuance costs	(115)	(103)
Total debt outstanding	13,899	12,672
Less: current portion	(649)	(649)
Long-term debt	$ 13,250	12,023
Senior Notes \| 2031 Notes
Debt Instrument [Line Items]
Stated Interest Rate	1.90%
Effective Interest Rate	1.981%
Long-term debt, gross	$ 600	0
Senior Notes \| 2051 Notes
Debt Instrument [Line Items]
Stated Interest Rate	2.95%
Effective Interest Rate	3.013%
Long-term debt, gross	$ 700	0
Senior Notes \| 2027 Notes
Debt Instrument [Line Items]
Stated Interest Rate	3.30%
Effective Interest Rate	3.42%
Long-term debt, gross	$ 1,000	1,000
Senior Notes \| 2030 Notes
Debt Instrument [Line Items]
Stated Interest Rate	3.35%
Effective Interest Rate	3.43%
Long-term debt, gross	$ 1,500	1,500
Senior Notes \| Senior Notes Due March 2050
Debt Instrument [Line Items]
Stated Interest Rate	3.85%
Effective Interest Rate	3.896%
Long-term debt, gross	$ 1,500	1,500
Senior Notes \| 2029 Notes
Debt Instrument [Line Items]
Stated Interest Rate	2.95%
Effective Interest Rate	3.03%
Long-term debt, gross	$ 1,000	1,000
Senior Notes \| 2049 Notes
Debt Instrument [Line Items]
Stated Interest Rate	3.65%
Effective Interest Rate	3.689%
Long-term debt, gross	$ 1,000	1,000
Senior Notes \| 2025 Notes [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.00%
Effective Interest Rate	2.147%
Long-term debt, gross	$ 750	750
Senior Notes \| 2028 Notes
Debt Instrument [Line Items]
Stated Interest Rate	3.50%
Effective Interest Rate	3.598%
Long-term debt, gross	$ 500	500
Senior Notes \| 2048 Notes
Debt Instrument [Line Items]
Stated Interest Rate	3.95%
Effective Interest Rate	3.99%
Long-term debt, gross	$ 500	500
Senior Notes \| 2021 Notes
Debt Instrument [Line Items]
Stated Interest Rate	2.00%
Effective Interest Rate	2.236%
Long-term debt, gross	$ 650	650
Senior Notes \| 2026 Notes
Debt Instrument [Line Items]
Stated Interest Rate	2.95%
Effective Interest Rate	3.044%
Long-term debt, gross	$ 750	750
Senior Notes \| 2046 Notes
Debt Instrument [Line Items]
Stated Interest Rate	3.80%
Effective Interest Rate	3.893%
Long-term debt, gross	$ 600	600
Senior Notes \| 2022 Notes
Debt Instrument [Line Items]
Stated Interest Rate	1.10%
Effective Interest Rate	1.265%
Long-term debt, gross	$ 833	859
Senior Notes \| 2.1% Notes due 2027
Debt Instrument [Line Items]
Stated Interest Rate	2.10%
Effective Interest Rate	2.189%
Long-term debt, gross	$ 953	982
Senior Notes \| 2.5% Notes due 2030
Debt Instrument [Line Items]
Stated Interest Rate	2.50%
Effective Interest Rate	2.562%
Long-term debt, gross	$ 178	184
Senior Notes \| 2024 Notes
Debt Instrument [Line Items]
Stated Interest Rate	3.375%
Effective Interest Rate	3.484%
Long-term debt, gross	$ 1,000	$ 1,000

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28541-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentUnamortizedDiscount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtLongtermAndShorttermCombinedAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebtCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant