Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Net deferred income tax assets	$ 29,000,000.0		$ 29,000,000.0		$ 45,000,000.0	$ 45,000,000.0
Foreign tax credit carryforwards	16,000.0		$ 16,000.0
Foreign tax credit carryforwards expiration year			2022
Decrease in deferred tax assets valuation allowance	16,000,000.0
Deferred tax assets valuation allowance	$ 29,000,000.0		$ 29,000,000.0		$ 45,000,000.0
Decrease in effective tax rate due to valuation allowance	49.00%		14.60%
Net benefit effective tax rate impact associated with stock-based compensation and prior tax reserves			0.60%
Effective tax rate increased		5.70%		6.50%
Decrease in effective tax rate		2.40%		4.80%
Decrease in unrecognized tax positions	$ 1,400,000		$ 1,400,000
Interest and penalties	$ 1,800,000		$ 1,800,000