EMPLOYEE COMPENSATION PLANS (Tables)

12 Months Ended

Dec. 31, 2023

EMPLOYEE COMPENSATION PLANS [Abstract]

Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

The following table presents the total equity-based compensation expense (stock options and RSUs) for the years ended December 31, 2023, 2022 and 2021 (in thousands):

	Year Ended December 31,
	2023		2022		2021
Equity-based compensation expense recognized in Cost of services	$	9,766	$	7,175	$	6,099
Equity-based compensation expense recognized in Selling, general and administrative		12,305		10,396		10,326
Total equity-based compensation expense	$	22,071	$	17,571	$	16,425
Total tax benefit recognized	$	2,329	$	5,512	$	8,673

Summary of non-vested RSU's and performance-based RSU's

		Weighted
		Average
		Grant Date
	Shares	Fair Value
Unvested as of December 31, 2022	1,358,723	$	65.37
Granted	729,076	$	33.34
Vested	(273,558)	$	61.90
Cancellations/expirations	(209,968)	$	63.78
Unvested as of December 31, 2023	1,604,273	$	51.61