Goodwill and Intangible Assets, Net - Summary of Changes in Net Carrying Amount of Goodwill (Details) $ in Millions	6 Months Ended
Jun. 30, 2022 USD ($)
Goodwill [Line Items]
Balance as of December 31, 2021	$ 3,638
Measurement period adjustments	(10)
Foreign currency translation	(4)
Balance as of June 30, 2022	3,624
Employer Solutions
Goodwill [Line Items]
Balance as of December 31, 2021	3,564
Measurement period adjustments	(10)
Foreign currency translation	(3)
Balance as of June 30, 2022	3,551
Professional Services
Goodwill [Line Items]
Balance as of December 31, 2021	74
Foreign currency translation	(1)
Balance as of June 30, 2022	$ 73

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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