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Cost-Reduction Actions - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 200,000		$ 5,400,000	$ 0
Charges related to work-force reductions	(500,000)		400,000
Benefit for changes in estimates		$ 900,000		3,100,000
Cost of revenue \| Services
Restructuring Cost and Reserve [Line Items]
Restructuring charges	(1,900,000)	700,000	(6,600,000)	4,200,000
Selling, general and administrative expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2,100,000	$ 200,000	10,700,000	$ (1,100,000)
Research and development expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges			1,300,000
Lease abandonment costs and asset write-offs
Restructuring Cost and Reserve [Line Items]
Other expenses related to the cost-reduction effort	$ 700,000		$ 5,000,000.0