Stock-Based Compensation - Additional Information (Detail) - USD ($)	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unamortized compensation cost, net of expected forfeitures	$ 200,000
Weighted average expected period over which the expense is to be recognized	2 years 3 months 18 days
Tax benefits associated with exercise of stock options	$ 0	$ 0
RSU's
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average expected period over which the expense is to be recognized	2 years 7 months 6 days
Unamortized compensation cost, net of expected forfeitures	$ 400,000
Stock options exercised	0	0
RSU's \| Equity Incentive Plan 2010
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total intrinsic value of the restricted stock units outstanding	$ 400,000
RSU's \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense, recognition period	3 years
RSU's \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense, recognition period	4 years

Allocated share based compensation expense period for recognition.

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- Definition

Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options

+ References

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- Definition

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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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

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

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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.

+ References

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- Definition

Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

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

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