Stock Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share Price	$ 5.03
Weighted average fair value of options to purchase common stock granted (in dollars per share)	3.30	$ 5.36
Weighted average fair value of stock options exercised (in dollars per share)	$ 1.69	$ 2.12
Intrinsic value of stock options exercised (in dollars)	$ 383	$ 1,200

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options exercised during the reporting period.

+ References

No definition available.

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