Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Billions	Sep. 30, 2024	Dec. 31, 2023
Cash equivalents	$ 3.6	$ 4.8
Investment, Type [Extensible Enumeration]	us-gaap:USTreasuryBillSecuritiesMember	us-gaap:USTreasuryBillSecuritiesMember

Indicates type of investment. Includes, but is not limited to, common stock, preferred stock, convertible security, fixed income security, government security, option purchased, warrant, loan participation and assignment, commercial paper, bankers' acceptance, certificates of deposit, short-term security, repurchase agreement, and other investment company.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details