Long-Term Debt (Details) - USD ($)	May 05, 2020	Jan. 31, 2020
Debt Instrument
Redemption price percentage	100.00%	100.00%
Senior Notes
Debt Instrument
Principal amount	$ 1,250,000,000	$ 1,250,000,000
Senior Notes \| 1.80% Senior Fixed-Rate Notes
Debt Instrument
Principal amount		$ 650,000,000
Interest rate		1.80%
Debt term		3 years
Senior Notes \| 2.25% Senior Fixed-Rate Notes
Debt Instrument
Principal amount		$ 600,000,000
Interest rate		2.25%
Debt term		7 years
Senior Notes \| 1.625% Senior Fixed-Rate Notes
Debt Instrument
Principal amount	$ 500,000,000
Interest rate	1.625%
Debt term	3 years
Senior Notes \| 1.625% Senior Fixed-Rate Notes \| Treasury Rate
Debt Instrument
Basis spread on variable rate (as a percent)	0.25%
Senior Notes \| 2.55% Senior Fixed-Rate Notes
Debt Instrument
Principal amount	$ 750,000,000
Interest rate	2.55%
Debt term	7 years
Senior Notes \| 2.55% Senior Fixed-Rate Notes \| Treasury Rate
Debt Instrument
Basis spread on variable rate (as a percent)	0.35%

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

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

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

+ References

Reference 1: 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 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

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Balance Type:	credit
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

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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

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Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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