Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Income Tax [Line Items]
Net deferred income tax assets		$ 49.7
Decrease in unrecognized tax positions	$ 1.9
Interest and penalties	1.8
ASU 2016-09 [Member]
Income Tax [Line Items]
Effective tax rate adjustment associated with stock compensation	$ 0.3
Percentage of decrease in effective tax rate associated with stock compensation	3.40%