Restructuring, Asset Impairment, and Transition Expenses - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 1,898,000	$ 1,553,000
Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost remaining	1,000,000
Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Expected restructuring cost remaining	3,500,000
Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	100,000	1,000,000
Consolidation costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	700,000
Moving and relocation [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	700,000
Building impairments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs		200,000
Travel-related and other restructuring costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 400,000	$ 300,000