Stock-Based Compensation - Summary of Stock Options (Detail) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) $ / shares shares
2013 Stock Incentive Plan
Stock Options
Beginning balance stock options, outstanding (in shares) \| shares	5,276,679
Stock options, granted (in shares) \| shares	0
Stock options, exercised (in shares) \| shares	0
Stock options, forfeited (in shares) \| shares	(674)
Stock options, expired (in shares) \| shares	(119,716)
Ending balance stock options, outstanding (in shares) \| shares	5,156,289
Stock options, exercisable (in shares) \| shares	4,141,636
Stock options, expected to vest after September 30, 2019 (in shares) \| shares	1,014,653
Stock options, exercisable as of September 30, 2019 and expected to vest (in shares) \| shares	5,156,289
Weighted- Average Exercise Price
Weighted - average exercise price, outstanding (in usd per share)	$ 10.57
Weighted - average exercise price, granted (in usd per share)	0
Weighted - average exercise price, exercised (in usd per share)	0
Weighted - average exercise price, forfeited (in usd per share)	11.10
Weighted - average exercise price, expired (in usd per share)	10.16
Weighted - average exercise price, outstanding (in usd per share)	10.58
Weighted - average exercise price exercisable at September 30, 2019 (in usd per share)	11.22
Weighted - average exercise price, expected to vest after September 30, 2019 (in usd per share)	7.97
Weighted - average exercise price, exercisable as of September 30, 2019 and expected to vest thereafter (in usd per share)	$ 10.58
Weighted - average remaining contractual term, outstanding	6 years 6 months
Weighted - average remaining contractual term, exercisable at September 30, 2019	6 years 1 month 6 days
Weighted - average remaining contractual term, expected to vest after September 30, 2019	8 years 4 months 24 days
Weighted - average remaining contractual term, exercisable as of September 30, 2019 and expected to vest thereafter	6 years 6 months
Aggregate intrinsic value, outstanding \| $	$ 0
Aggregate intrinsic value, exercisable at September 30, 2019 \| $	0
Aggregate intrinsic value, expected to vest after September 30, 2019 \| $	0
Aggregate intrinsic value, exercisable as of September 30, 2019 and expected to vest thereafter \| $	$ 0
Estimated fair value of the Company's common stock (in usd per share)	$ 1.93
2011 Stock Incentive Plan
Stock Options
Beginning balance stock options, outstanding (in shares) \| shares	533,547
Stock options, granted (in shares) \| shares	0
Stock options, exercised (in shares) \| shares	(3,597)
Stock options, forfeited (in shares) \| shares	(1,277)
Stock options, expired (in shares) \| shares	(26,694)
Ending balance stock options, outstanding (in shares) \| shares	501,979
Stock options, exercisable (in shares) \| shares	492,688
Stock options, expected to vest after September 30, 2019 (in shares) \| shares	9,291
Stock options, exercisable as of September 30, 2019 and expected to vest (in shares) \| shares	501,979
Weighted- Average Exercise Price
Weighted - average exercise price, outstanding (in usd per share)	$ 8.83
Weighted - average exercise price, granted (in usd per share)	0
Weighted - average exercise price, exercised (in usd per share)	3.68
Weighted - average exercise price, forfeited (in usd per share)	9.43
Weighted - average exercise price, expired (in usd per share)	7.74
Weighted - average exercise price, outstanding (in usd per share)	8.92
Weighted - average exercise price exercisable at September 30, 2019 (in usd per share)	8.92
Weighted - average exercise price, expected to vest after September 30, 2019 (in usd per share)	9.09
Weighted - average exercise price, exercisable as of September 30, 2019 and expected to vest thereafter (in usd per share)	$ 8.92
Weighted - average remaining contractual term, outstanding	1 year 8 months 12 days
Weighted - average remaining contractual term, exercisable at September 30, 2019	1 year 8 months 12 days
Weighted - average remaining contractual term, expected to vest after September 30, 2019	3 years 6 months
Weighted - average remaining contractual term, exercisable as of September 30, 2019 and expected to vest thereafter	1 year 8 months 12 days
Aggregate intrinsic value, outstanding \| $	$ 0
Aggregate intrinsic value, exercisable at September 30, 2019 \| $	0
Aggregate intrinsic value, expected to vest after September 30, 2019 \| $	0
Aggregate intrinsic value, exercisable as of September 30, 2019 and expected to vest thereafter \| $	$ 0
Estimated fair value of the Company's common stock (in usd per share)	$ 1.93

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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