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Fair Value Measurements (Details 1) - USD ($)	1 Months Ended
	Feb. 28, 2021	Mar. 31, 2021	Dec. 31, 2020	Apr. 30, 2020
Debt Instrument [Line Items]
Notes payable, carrying value		$ 7,267,200,000	$ 7,426,200,000
Debt instruments, fair value		$ 7,859,200,000	8,515,900,000
2.900% Senior Notes due 2020
Debt Instrument [Line Items]
Senior notes interest rate		2.90%
3.625% Senior Notes due 2022
Debt Instrument [Line Items]
Notes payable, fair value		$ 1,044,200,000	1,054,100,000
Notes payable, carrying value		$ 998,200,000	997,900,000
Senior notes interest rate		3.625%
4.050% Senior Notes due 2025
Debt Instrument [Line Items]
Notes payable, fair value		$ 1,940,800,000	2,003,100,000
Notes payable, carrying value		$ 1,741,500,000	1,741,200,000
Senior notes interest rate		4.05%
2.250% Senior Notes due May 1, 2030
Debt Instrument [Line Items]
Notes payable, fair value		$ 1,455,300,000	1,557,200,000
Notes payable, carrying value		$ 1,491,400,000	1,491,100,000
Senior notes interest rate		2.25%
5.200% Senior Notes due 2045
Debt Instrument [Line Items]
Notes payable, fair value		$ 1,394,800,000	2,365,100,000
Notes payable, carrying value		$ 1,099,700,000	1,723,400,000
Senior notes interest rate		5.20%
Long Term Debt, Exchanged, Amount	$ 624,600,000
3.150% Senior Notes due May 1, 2050
Debt Instrument [Line Items]
Notes payable, fair value		$ 1,369,800,000	1,536,400,000
Notes payable, carrying value		$ 1,472,700,000	1,472,600,000
Senior notes interest rate		3.15%
3.250% Senior Notes, Due February 15, 2051
Debt Instrument [Line Items]
Notes payable, fair value		$ 654,300,000	0
Notes payable, carrying value		$ 463,700,000	$ 0
Senior notes interest rate		3.25%
Long Term Debt, Exchanged, Amount	$ 700,700,000
Senior Notes
Debt Instrument [Line Items]
Face amount				$ 3,000,000,000.0
Senior Notes | 2.250% Senior Notes due May 1, 2030
Debt Instrument [Line Items]
Senior notes interest rate				2.25%
Face amount				$ 1,500,000,000
Senior Notes | 3.150% Senior Notes due May 1, 2050
Debt Instrument [Line Items]
Senior notes interest rate				3.15%
Face amount				$ 1,500,000,000

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