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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Goodwill and Other Intangible Assets, Net - Additional Information (Detail)		12 Months Ended
	Nov. 01, 2019 USD ($) Reporting_Unit	Dec. 31, 2019 USD ($) Reporting_Unit	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Finite-Lived Intangible Assets [Line Items]
Number of reporting units \| Reporting_Unit	5	5
Goodwill impairment	$ 0
Intangible assets amortization period		6 years 6 months
2020		$ 13,100,000
2021		11,600,000
2022		9,900,000
2023		8,700,000
2024		$ 7,600,000
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period		2 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period		15 years
Client Lists and Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ 14,100,000	$ 17,500,000	$ 17,800,000
Client Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period		6 years 9 months 18 days
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period		6 years 8 months 12 days
Other Intangible Assets [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period		2 years
Other Intangible Assets [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period		10 years