Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unamortized compensation cost, net of expected forfeitures	$ 1,000,000
Weighted average expected period over which the expense is to be recognized	2 years 2 months 12 days
Tax benefits associated with exercise of stock options	$ 0	$ 0
Dividend yield (as a percent)		0.00%
Stock options exercised	0	0
Options Outstanding, Aggregate Intrinsic Value	$ 70,000
RSU's
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unamortized compensation cost, net of expected forfeitures	$ 500,000
Weighted average expected period over which the expense is to be recognized	10 months 24 days
Cash paid for employee income tax related to settlement of RSUs	$ 38,000
RSU's \| Equity Incentive Plan2010 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total intrinsic value of the restricted stock units outstanding	$ 300,000
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	5 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

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Intrinsic value of equity-based compensation awards outstanding. Excludes stock 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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