STOCK-BASED COMPENSATION (Tables)

12 Months Ended

Mar. 31, 2024

STOCK-BASED COMPENSATION

Stock-based compensation cost associated with employees

					Three Months
					Ended		Year Ended
	Year Ended March 31,				March 31,		December 31,
(Dollars in millions)	2024		2023		2022		2021
Cost of services	$	16	$	21	$	7	$	28
Selling, general and administrative expense		78		92		24		44
Pretax stock-based compensation expense	$	95	$	113	$	31	$	71
Income tax benefits		(5)		(5)		(5)		(13)
Stock-based compensation cost, net of tax	$	90	$	108	$	26	$	58

Summary of restricted stock units, market-conditioned stock units, and performance-conditioned stock units activity

					Market-Conditioned				Performance-Conditioned
	RSUs				Stock Units				Stock Units*
			Weighted-				Weighted-				Weighted-
			Average				Average				Average
	Number		Grant-Date		Number		Grant-Date		Number		Grant-Date
	of Units		Fair Value		of Units		Fair Value		of Units		Fair Value
	(in millions)		(per share)		(in millions)		(per share)		(in millions)		(per share)
Nonvested balance at December 31, 2021		10.2	$	26.82		1.8	$	15.14		—	$	—
Awards granted		0.4		17.61		—		—		—		—
Awards vested		(0.5)		28.04		—		—		—		—
Awards canceled/forfeited		(0.2)		28.44		—		—		—		—
Nonvested balance at March 31, 2022		9.8	$	26.36		1.8	$	15.14		—	$	—
Awards granted		5.0	$	10.80		0.7	$	12.51		2.5	$	10.62
Awards vested		(4.9)		26.09		—		—		—		—
Awards canceled/forfeited		(0.5)		23.09		(0.2)		14.46		(0.1)		10.62
Nonvested balance at March 31, 2023		9.4	$	18.43		2.3	$	14.40		2.3	$	10.62
Awards granted		3.1	$	13.52		0.6	$	14.10		2.0	$	13.37
Awards vested		(4.0)		21.92		—		—		—		—
Awards canceled/forfeited		(0.4)		17.43		(0.1)		14.43		(0.1)		11.85
Nonvested balance at March 31, 2024		8.0	$	15.33		2.9	$	14.32		4.3	$	12.28

* The grant-date fair value of performance-conditioned stock units issued was determined using the stock price at the grant date.

Summary of assumptions used in estimation of fair value of market-conditioned stock units

	Year Ended
	March 31,	March 31,	December 31,
Market-conditioned Stock Units:	2024	2023	2021
Share price	$13.55	$10.89	$18.31
Expected volatility*	39%	39%	35%
Risk-free interest rate	4.57% - 5.38%	2.85%	0.26% - 0.92%
Dividend yield	0%	0%	0%

* Based on the average unadjusted three-year historic volatility across a group of peer companies.

Summary of stock option activity

	Stock Options
									Weighted-
					Weighted-				Average
			Weighted-		Average		Aggregate		Remaining
	Number		Average		Grant Date		Intrinsic		Contractual
	of Units		Exercise Price		Fair Value		Value		Term
	(in millions)		(per share)		(per share)		(in millions)		(in years)
Outstanding balance at December 31, 2021		3.8	$	17.76	$	6.54		—	10.0
Awards exercised		—		—		—
Awards canceled/forfeited		—		—		—
Outstanding balance at March 31, 2022		3.8	$	17.76	$	6.54	$	—	9.7
Awards exercised		—		—		—
Awards canceled/forfeited		(0.2)		17.78		6.54
Outstanding balance at March 31, 2023		3.7	$	17.76	$	6.54	$	—	8.7
Awards exercised		(0.0)		17.30		6.61
Awards canceled/forfeited		(0.1)		17.78		6.54
Outstanding balance at March 31, 2024		3.5	$	17.77	$	6.54	$	14.2	7.3
Options vested and exercisable at March 31, 2024		1.9		17.76		6.54		7.8	6.9

Summary of assumptions used in estimation of fair value of stock options

	Year Ended
	December 31,
Employee Stock Options:	2021
Fair value of common stock per share	$17.78
Expected term (in years)*	6.25
Expected volatility**	34.5%
Risk-free interest rate	1.4%
Dividend yield	0.0%

* The Company utilized the simplified method to estimate the weighted-average option term due to a lack of relevant historical data.

** Based on the average unadjusted historic volatility of common shares across a group of peer companies.