Summary of Lease Exit and Severance Liabilities (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Restructuring Cost And Reserve [Line Items]
Beginning balance	$ 6,753
Charges	3,651
Cash payments	(4,097)
Ending balance	6,307
Lease Exit Costs
Restructuring Cost And Reserve [Line Items]
Beginning balance	6,468
Cash payments	(844)
Ending balance	5,624
Severance
Restructuring Cost And Reserve [Line Items]
Beginning balance	285
Charges	3,651
Cash payments	(3,253)
Ending balance	$ 683

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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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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