Restructuring - Schedule of Components of the Restructuring Liabilities (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 8,777	$ 8,777
Stock-Based Compensation Expense
Restructuring Cost And Reserve [Line Items]
Restructuring charges		$ 4,100

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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-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration