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Stock Plans - Additional Information (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	Jun. 22, 2015 USD ($) $ / shares shares	May. 22, 2015 $ / shares shares	May. 07, 2015
Options To Purchase Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding \| shares	734	1,700
Percentage of options eligible for exchange		99.60%
weighted-average exercise price	$ 5.25	$ 24.68
Vesting period	3 years
Stock option expense \| $	$ 1,599
Options To Purchase Common Stock \| Vesting on the first anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Options To Purchase Common Stock \| Vesting on the second anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Options To Purchase Common Stock \| Vesting on the third anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
Employees \| Stock Incentive Plan 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock conversion ratio			2
Chief Executive Officer \| Stock Incentive Plan 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock conversion ratio			3.5