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Restructuring and Related Charges - Schedule of Accrued Restructuring and Related Charges Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost And Reserve [Line Items]
Restructuring and related charges	$ 7,024	$ 124	$ 3,223
2019 Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Restructuring and related charges	7,000
Accrued restructuring and related charges liability as of December 31, 2019	17,500
2019 Restructuring Plan \| Severance and Other Employee-Related Costs
Restructuring Cost And Reserve [Line Items]
Restructuring and related charges	5,476
Payments	(2,453)
Accrued restructuring and related charges liability as of December 31, 2019	$ 3,023