Segment Information - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) Segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment	2
Percentage of total revenue	13.00%	16.00%	16.00%
Depreciation and amortization	$ 64.4	$ 73.8	$ 76.3
Other general and administrative expense			1.8
Other Segments
Segment Reporting Information [Line Items]
Other general expense		1.4	$ 1.8
Other general and administrative expense	$ 1.2	$ 0.8

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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