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

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

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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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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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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)	Jul. 31, 2021 USD ($)	Jan. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Oct. 31, 2020 USD ($)	Jul. 31, 2020 USD ($)	May 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	May 31, 2019 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 GBP (£)	Jul. 31, 2021 GBP (£)	Oct. 31, 2020 GBP (£)	May 31, 2019 GBP (£)
Unsecured debt \| Credit Facility
Debt
Maximum borrowing capacity				$ 3,000,000,000					$ 3,000,000,000
1.125% Notes due 2027 \| Notes payable
Debt
Interest rate (as a percent)									1.125%	1.125%	1.125%
Principal amount \| £										£ 400,000,000	£ 400,000,000
Proceeds from issuance of debt	$ 546,300,000
1.750% Notes due 2033 \| Notes payable
Debt
Interest rate (as a percent)									1.75%	1.75%	1.75%
Principal amount \| £										£ 350,000,000	£ 350,000,000
Proceeds from issuance of debt	$ 480,600,000
1.800% Notes due 2033 \| Notes payable
Debt
Interest rate (as a percent)			1.80%						1.80%	1.80%
Principal amount			$ 400,000,000						$ 400,000,000
Proceeds from issuance of debt			$ 391,300,000
0.750% Notes due 2026 \| Notes payable
Debt
Interest rate (as a percent)			0.75%						0.75%	0.75%
Principal amount			$ 325,000,000						$ 325,000,000
Proceeds from issuance of debt			$ 320,300,000
3.250% Notes due 2022 \| Notes payable
Debt
Interest rate (as a percent)		3.25%	3.25%
Principal amount			$ 950,000,000
Early redemption of notes		$ 950,000,000
1.625% Notes due 2030 \| Notes payable
Debt
Interest rate (as a percent)				1.625%					1.625%	1.625%		1.625%
Principal amount \| £										£ 400,000,000		£ 400,000,000
Proceeds from issuance of debt				$ 508,200,000
3.250% Notes, issued July 2020, due 2031 \| Notes payable
Debt
Interest rate (as a percent)					3.25%
Principal amount					$ 350,000,000				$ 350,000,000
Proceeds from issuance of debt					$ 376,600,000
3.250% Notes, issued May 2020, due 2031 \| Notes payable
Debt
Interest rate (as a percent)						3.25%
Principal amount						$ 600,000,000			$ 600,000,000
Proceeds from issuance of debt						$ 590,000,000
2.730% Notes due 2034 \| Notes payable
Debt
Interest rate (as a percent)									2.73%	2.73%			2.73%
Principal amount \| £										£ 315,000,000			£ 315,000,000
Proceeds from issuance of debt								$ 400,900,000
3.250% Notes due 2029 \| Notes payable
Debt
Interest rate (as a percent)							3.25%		3.25%	3.25%
Principal amount							$ 500,000,000		$ 500,000,000
Proceeds from issuance of debt							$ 493,500,000