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Restructuring - Additional Information (Detail)	Mar. 20, 2017 Employee	Mar. 19, 2017 USD ($) Employee	Mar. 31, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
Amount paid under terms of the retention agreements			$ 1,069,000
Percentage of workforce termination	58.00%
Total number of full-time equivalent employees remaining | Employee	8	19
Certain Key Employees [Member]
Restructuring Cost and Reserve [Line Items]
Amount paid under terms of the retention agreements			$ 1,100,000
Certain Key Employees [Member] | Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Retention agreements period of salary compensation as lump sum payments (in months)		3 months
Certain Key Employees [Member] | Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Retention agreements period of salary compensation as lump sum payments (in months)		18 months
Amount required to pay under retention agreements		$ 1,600,000

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- Definition

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- Definition

Restructuring and related cost number of positions remaining.

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- Definition

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- Definition

Amount of expected cost remaining for the specified restructuring cost.

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- Definition

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

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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