Goodwill and Intangible Assets, Net - Summary of Changes in Net Carrying Amount of Goodwill (Details) $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($)
Goodwill [Line Items]
Balance as of December 31, 2022	$ 3,679
Foreign currency translation	1
Balance as of March 31, 2023	3,680
Employer Solutions
Goodwill [Line Items]
Balance as of December 31, 2022	3,606
Foreign currency translation	1
Balance as of March 31, 2023	3,607
Professional Services
Goodwill [Line Items]
Balance as of December 31, 2022	73
Balance as of March 31, 2023	$ 73