v3.21.2

Goodwill and Intangible Assets, Net - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Jul. 01, 2021	Dec. 31, 2020
Finite Lived Intangible Assets [Line Items]
Goodwill	$ 3,356,000,000		$ 2,250,000,000	$ 3,356,000,000			$ 2,245,000,000
Non-taxable portion of goodwill acquired during period				1,500,000,000
Impairment of goodwill	0		0	0
Amortization of intangible assets	74,000,000	$ 51,000,000	100,000,000		$ 151,000,000
Accumulated amortization	74,000,000			74,000,000		$ 0	$ 672,000,000
Employer Solutions
Finite Lived Intangible Assets [Line Items]
Goodwill			$ 3,400,000,000
Professional Services
Finite Lived Intangible Assets [Line Items]
Goodwill	$ 36,000,000			$ 36,000,000

X

- Definition

Goodwill acquired during period non taxable.

+ References

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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