INVESTMENTS - Summary of Investments by Major Security Type (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt securities:
Carrying Value	$ 0	$ 576
Equity securities:
Cost	826	793
Gross Unrealized Gains /Upward Adjustments	259	259
Gross Unrealized Losses /Downward Adjustments	(585)	(612)
Carrying Value	500	440
Short-term Investments
Debt securities:
Cost		580
Gross Unrealized Gains /Upward Adjustments		0
Gross Unrealized Losses /Downward Adjustments		(4)
Carrying Value		576
International government securities \| Short-term Investments
Debt securities:
Cost		63
Gross Unrealized Gains /Upward Adjustments		0
Gross Unrealized Losses /Downward Adjustments		0
Carrying Value		63
U.S. government securities \| Short-term Investments
Debt securities:
Cost		152
Gross Unrealized Gains /Upward Adjustments		0
Gross Unrealized Losses /Downward Adjustments		(1)
Carrying Value		151
Corporate debt securities \| Short-term Investments
Debt securities:
Cost		365
Gross Unrealized Gains /Upward Adjustments		0
Gross Unrealized Losses /Downward Adjustments		(3)
Carrying Value		362
Equity securities with readily determinable fair values \| Long-term Investments
Equity securities:
Cost	715	715
Gross Unrealized Gains /Upward Adjustments	0	0
Gross Unrealized Losses /Downward Adjustments	(360)	(404)
Carrying Value	355	311
Equity securities of private entities \| Long-term Investments
Equity securities:
Cost	111	78
Gross Unrealized Gains /Upward Adjustments	259	259
Gross Unrealized Losses /Downward Adjustments	(225)	(208)
Carrying Value	$ 145	$ 129

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