STOCK BASED COMPENSATION - Schedule of Stock Based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Additional Disclosures for equity-based plans
Total stock based compensation expense	$ 59	$ 62	$ 50
Total stock based compensation capitalized	3	1	1
Income tax benefit related to stock based compensation expense	13	13	10
Tax benefit realized	19	14	16
Cost of providing services
Additional Disclosures for equity-based plans
Total stock based compensation expense	14	13	12
Sales and marketing
Additional Disclosures for equity-based plans
Total stock based compensation expense	8	7	6
General and administrative
Additional Disclosures for equity-based plans
Total stock based compensation expense	33	38	29
Systems development and programming costs
Additional Disclosures for equity-based plans
Total stock based compensation expense	$ 4	$ 4	$ 3