Stock-Based Compensation - Summary of Option Activity (Detail) - $ / shares shares in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares, Outstanding, Beginning balance	1,257
Shares, Granted	0
Shares, Exercised	0
Shares, Expired	(108)
Shares, Forfeited	(58)
Shares, Outstanding, Ending balance	1,091	1,257
Shares, Vested and expected to vest	1,051
Shares, Exercisable, Ending balance	884
Wtd. Avg. Exercise Price Outstanding, Beginning balance	$ 1.04
Wtd. Avg. Exercise Price, Granted	0
Wtd. Avg. Exercise Price, Exercised	0
Wtd. Avg. Exercise Price, Expired	0.51
Wtd. Avg. Exercise Price, Forfeited	1.81
Wtd. Avg. Exercise Price, Outstanding, Ending balance	1.05	$ 1.04
Wtd. Avg. Exercise Price, Vested and expected to vest	1.03
Wtd. Avg. Exercise Price, Exercisable, Ending balance	$ 0.94
Wtd. Avg. Remaining Contractual Life, Outstanding	4 years 26 days	4 years 6 months 4 days
Wtd. Avg. Remaining Contractual Life, Vested and expected to vest	4 years 11 days
Wtd. Avg. Remaining Contractual Life, Exercisable	3 years 7 months 24 days

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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-Publisher FASB
-Name Accounting Standards Codification
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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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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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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options that are exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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