Restructuring and Other - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($) employee	Jun. 30, 2017 USD ($) employee	Jun. 30, 2018 USD ($) employee	Jun. 30, 2017 USD ($) employee
Reorganizations [Abstract]
Restructuring and other costs	$ 3,024	$ 3,671	$ 7,678	$ 4,589
Severance charges	$ 1,300	$ 3,100	$ 4,400	$ 3,500
Number of positions eliminated | employee	28	83	95	113
Facilities relocation and downsizing expenses	$ 500	$ 200	$ 1,000	$ 200
Integration expenses	$ 1,100	$ 400	$ 2,300	$ 800