Contingencies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Accrued other long-term liabilities	$ 7.3		$ 7.3
Estimated sales and marketing expense (benefit)	(0.1)	$ (0.5)	0.4	$ 0.7
Freezing amount in cash resulted from court pending legal action issued	0.6		0.6
Accruals related court pending legal dispute	$ 1.7		$ 1.7