The percentage of the principal amount of the bonds which was paid by the investors.

No definition available.

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- 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
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-Section 55
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- 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)
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-Name Accounting Standards Codification
-Topic 210
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
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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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Notes Payable - Note Issuances (Details) - Notes payable	Dec. 31, 2020 USD ($)	Oct. 31, 2020 GBP (£)	Jul. 31, 2020 USD ($)	May 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	May 31, 2019 GBP (£)	Apr. 30, 2018 USD ($)
3.250% notes, issued in May 2020 and due in January 2031
Debt
Stated interest rate (as a percent)				3.25%
Face amount of notes				$ 600,000,000
Price of par value (as a percent)				98.99%
Effective yield (as a percent)				3.36%
3.250% notes, issued in July 2020 and due in January 2031
Debt
Stated interest rate (as a percent)			3.25%
Face amount of notes			$ 350,000,000
Price of par value (as a percent)			108.24%
Effective yield (as a percent)			2.34%
1.625% notes, issued in October 2020 and due December 2030
Debt
Stated interest rate (as a percent)	1.625%	1.625%
Face amount of notes \| £		£ 400,000,000
Price of par value (as a percent)		99.19%
Effective yield (as a percent)		1.71%
0.750% notes, issued in December 2020 and due in March 2026
Debt
Stated interest rate (as a percent)	0.75%
Face amount of notes	$ 325,000,000.0
Price of par value (as a percent)	99.19%
Effective yield (as a percent)	0.91%
1.800% notes, issued in December 2020 and due in March 2033
Debt
Stated interest rate (as a percent)	1.80%
Face amount of notes	$ 400,000,000.0
Price of par value (as a percent)	98.47%
Effective yield (as a percent)	1.94%
2.730% notes, issued in May 2019 and due in May 2034
Debt
Stated interest rate (as a percent)	2.73%					2.73%
Face amount of notes \| £						£ 315,000,000
Price of par value (as a percent)						100.00%
Effective yield (as a percent)						2.73%
3.250% notes, issued in June 2019 and due in June 2029
Debt
Stated interest rate (as a percent)	3.25%				3.25%
Face amount of notes					$ 500,000,000
Price of par value (as a percent)					99.36%
Effective yield (as a percent)					3.33%
3.875% notes, issued in April 2018 and due in April 2025
Debt
Stated interest rate (as a percent)	3.875%						3.875%
Face amount of notes							$ 500,000,000
Price of par value (as a percent)							99.50%
Effective yield (as a percent)							3.96%