Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, non-employee directors (in shares)	503,950	1,212,200
Weighted-average grant-date fair value of options and awards	$ 2.55	$ 4.24
Total fair value of options and awards that vested	$ 1.3	$ 1.0
Unrecognized stock-based compensation expense	$ 4.2
Weighted-average period of unrecognized stock-based compensation expense	3 years
Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, non-employee directors (in shares)	32,500
New Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
2012 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vested period	4 years
Options or awards issued under the Plan (in shares)	0
2012 Stock Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options grant period	10 years
2014 Equity and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vested period	4 years
2014 Equity and Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options grant period	10 years

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of shares issued under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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