Restructuring Charges - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2019
Restructuring And Related Activities [Abstract]
Lease term expiration			lease terms expiring between 2023 and 2026
Lease exit charge		$ 5.5
severance charge	$ 3.8	$ 1.8

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	duration