TRANSITION PERIOD - Income Statement - Related Party (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Mar. 31, 2022		Mar. 31, 2021	Mar. 31, 2024		Mar. 31, 2023		Dec. 31, 2021
Revenue	$ 4,431	[1]	$ 4,771	$ 16,052	[1]	$ 17,026	[1]	$ 18,657	[1]
Cost of services	3,824	[2]	4,318	$ 13,189	[2]	14,498	[2]	16,550	[2]
Related Party
Revenue	236		154			287		704
Cost of services	$ 924		$ 1,006			$ 1,382		$ 3,979

[1] Including related-party revenue of $287 for the year ended March 31, 2023, $236 for the three months ended March 31, 2022, and $704 for the year ended December 31, 2021

[2] Including related-party cost of service of $1,382 for the year ended March 31, 2023, $924 for the three months ended March 31, 2022, and $3,979 for the year ended December 31, 2021