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

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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.

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No definition available.

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Notes Payable - Note Issuances Narrative (Details)	1 Months Ended
Notes Payable - Note Issuances Narrative (Details)	Jan. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Oct. 31, 2020 USD ($)	Jul. 31, 2020 USD ($)	May 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	May 31, 2019 USD ($)	Apr. 30, 2018 USD ($)	Oct. 31, 2020 GBP (£)	May 31, 2019 GBP (£)
Notes payable \| 1.800% notes, issued in December 2020 and due in March 2033
Debt
Proceeds from issuance of debt		$ 391,300,000
Stated interest rate (as a percent)		1.80%
Face amount of loan		$ 400,000,000.0
Notes payable \| 0.750% notes, issued in December 2020 and due in March 2026
Debt
Proceeds from issuance of debt		$ 320,300,000
Stated interest rate (as a percent)		0.75%
Face amount of loan		$ 325,000,000.0
Notes payable \| 3.250% notes due in October 2022
Debt
Stated interest rate (as a percent)		3.25%
Notes payable \| 3.250% notes due in October 2022 \| Subsequent event
Debt
Early repayment of notes payable	$ 950,000,000.0
Stated interest rate (as a percent)	3.25%
Notes payable \| 1.625% notes, issued in October 2020 and due December 2030
Debt
Proceeds from issuance of debt			$ 508,200,000
Stated interest rate (as a percent)		1.625%	1.625%						1.625%
Face amount of loan \| £									£ 400,000,000
Notes payable \| 3.250% notes, issued in July 2020 and due in January 2031
Debt
Proceeds from issuance of debt				$ 376,600,000
Stated interest rate (as a percent)				3.25%
Face amount of loan				$ 350,000,000
Notes payable \| 3.250% notes, issued in May 2020 and due in January 2031
Debt
Proceeds from issuance of debt					$ 590,000,000.0
Stated interest rate (as a percent)					3.25%
Face amount of loan					$ 600,000,000
Notes payable \| 2.730% notes, issued in May 2019 and due in May 2034
Debt
Proceeds from issuance of debt							$ 400,900,000
Stated interest rate (as a percent)		2.73%								2.73%
Face amount of loan \| £										£ 315,000,000
Notes payable \| 3.250% notes, issued in June 2019 and due in June 2029
Debt
Proceeds from issuance of debt						$ 493,500,000
Stated interest rate (as a percent)		3.25%				3.25%
Face amount of loan						$ 500,000,000
Notes payable \| 3.875% notes, issued in April 2018 and due in April 2025
Debt
Proceeds from issuance of debt								$ 494,400,000
Stated interest rate (as a percent)		3.875%						3.875%
Face amount of loan								$ 500,000,000
Unsecured debt \| Credit Facility
Debt
Maximum borrowing capacity		$ 3,000,000,000.0	$ 3,000,000,000.0