Restructuring and Related Charges - Schedule of Accrued Restructuring and Related Charges Activity (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost And Reserve [Line Items]
Restructuring and related charges	$ 281	$ 4,225	$ 124
2019 Restructuring Plan
Restructuring Cost And Reserve [Line Items]
Restructuring and related charges	300	4,200
Accrued restructuring and related charges liability as of September 30, 2019	10,300	10,300
2019 Restructuring Plan \| Severance and Other Employee-Related Costs
Restructuring Cost And Reserve [Line Items]
Restructuring and related charges		3,583
Payments		(1,706)
Accrued restructuring and related charges liability as of September 30, 2019	$ 1,877	$ 1,877

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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