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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The number of positions eliminated during the period as a result of restructuring activities.

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No definition available.

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The number of positions eliminated during the period as a percentage of total positions eliminated during the period in connection with the restructuring plan(s).

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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
-Subparagraph (b)
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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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Restructuring Charges - Additional Information (Detail) $ in Millions			12 Months Ended
	Dec. 31, 2015 USD ($)	Sep. 30, 2015 Employee	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Restructuring Cost and Reserve [Line Items]
Percentage of workforce reduction		26.00%
Number of employees eliminated \| Employee		198
Restructuring charges			$ 5.9	$ 1.9	$ 0.4
Payment to restructuring	$ 2.8
Restucturing accrual	$ 3.0		3.0	$ 0.3	$ 0.0
Research and development
Restructuring Cost and Reserve [Line Items]
Restructuring charges			3.0
General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 2.9