Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

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

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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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- Definition

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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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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Restructuring Actions - Additional Information (Detail)	1 Months Ended	12 Months Ended
Restructuring Actions - Additional Information (Detail)	Sep. 30, 2016 Employee	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Restructuring Cost And Reserve [Line Items]
Proceeds from sale of equipment		$ 890,000	$ 0
Gain on sale of equipment		600,000	0
R&D Expense
Restructuring Cost And Reserve [Line Items]
Restructuring charges		1,000,000	$ 0
Interest and Other Income
Restructuring Cost And Reserve [Line Items]
Gain on sale of equipment		600,000
Employee Severance and Benefits
Restructuring Cost And Reserve [Line Items]
Reduction in workforce \| Employee	10
Percentage of workforce reduced	50.00%
Restructuring charges		900,000
Legal and Facility Expenses
Restructuring Cost And Reserve [Line Items]
Restructuring charges		$ 100,000