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Related Party Transactions (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended				9 Months Ended
	Aug. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Related Party Transaction [Line Items]
Operating expenses		$ 503			$ 3,018	$ 1,544	$ 3,858
Prepaid expenses and other current assets		118				118		$ 129
Accounts payable		69				$ 69		72
Stock repurchased and retired during period, value		$ 362	$ 325	$ 715
Stock Repurchase Program - June 2024
Related Party Transaction [Line Items]
Repurchase and retirement of common stock (in shares)		10,782,385				13,069,383
Stock repurchased and retired during period, value		$ 362				$ 437
Related Party
Related Party Transaction [Line Items]
Related party transaction, amounts of transaction				0	0
Operating expenses				$ 8	$ 7		$ 18
Prepaid expenses and other current assets								13
Accounts payable								$ 0
Related Party \| Stock Repurchase Program - June 2024
Related Party Transaction [Line Items]
Repurchase and retirement of common stock (in shares)	3,700,000
Stock repurchased and retired during period, value	$ 117