Debt - Summary of Debt Issuances (Details) - USD ($)	Mar. 03, 2021	Sep. 30, 2021
Senior Notes
Debt Instrument [Line Items]
Principal	$ 4,300,000,000
$500 million, 0.613% Notes due 2024
Debt Instrument [Line Items]
Interest rate		0.613%
$500 million, 0.613% Notes due 2024 | Senior Notes
Debt Instrument [Line Items]
Principal	$ 500,000,000
Interest rate	0.613%
Net proceeds	$ 499,000,000
$800 million, 1.25% Notes due 2026
Debt Instrument [Line Items]
Interest rate		1.25%
$800 million, 1.25% Notes due 2026 | Senior Notes
Debt Instrument [Line Items]
Principal	$ 800,000,000
Interest rate	1.25%
Net proceeds	$ 797,000,000
$1,500 million, 2.375% Notes due 2031 (1)
Debt Instrument [Line Items]
Interest rate		2.375%
$1,500 million, 2.375% Notes due 2031 (1) | Senior Notes
Debt Instrument [Line Items]
Principal	$ 1,500,000,000
Interest rate	2.375%
Net proceeds	$ 1,492,000,000
$1,500 million , 3.4% Notes due 2051
Debt Instrument [Line Items]
Interest rate		3.40%
$1,500 million , 3.4% Notes due 2051 | Senior Notes
Debt Instrument [Line Items]
Principal	$ 1,500,000,000
Interest rate	3.40%
Net proceeds	$ 1,479,000,000