Financial Instruments - Forward Starting Derivatives (Details) - Designated as Hedging Instrument - Forward Interest Rate Swap	Dec. 31, 2020 USD ($)
Derivative [Line Items]
Derivative, notional amount	$ 1,050,000
Unsecured Senior Notes In Fiscal 2022
Derivative [Line Items]
Derivative, notional amount	$ 450,000
Interest rate	1.33%
Unsecured Senior Notes In Fiscal 2023
Derivative [Line Items]
Derivative, notional amount	$ 300,000
Interest rate	1.36%
Unsecured Senior Notes In Fiscal 2025
Derivative [Line Items]
Derivative, notional amount	$ 300,000
Interest rate	1.35%

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

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

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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.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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