Restructuring Plan - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Restructuring And Related Activities [Abstract]
Restructuring cost	$ 0	$ 75	$ 655	$ 1,900
Non-cash stock-based compensation				$ 181

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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Data Type:	xbrli:monetaryItemType
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Period Type:	duration