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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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 (c)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

+ Details

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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ 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 (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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 (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

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- Definition

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

+ 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Stock-Based Compensation (Details) - $ / shares	12 Months Ended
Stock-Based Compensation (Details) - $ / shares	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of options outstanding by exercise price range
Options Exercisable, Weighted Average Exercise Price		$ 0.67	$ 1.24
Stock Options [Member]
Summary of options outstanding by exercise price range
Options Outstanding, Number Outstanding at 12/31/17	1,756,000
Options outstanding, Weighted Average Remaining Contractual Life (years)	2 years 2 months 5 days
Options Outstanding, Weighted Average Exercise Price	$ 4.20
Options Exercisable, Number Exercisable at 12/31/17	1,746,000
Options Exercisable, Weighted Average Exercise Price	$ 4.21
Stock Options [Member] \| Range one [Member]
Summary of options outstanding by exercise price range
Range of Exercise Price, Lower Range Limit	1.44
Range of Exercise Price, Upper Range Limit	$ 3.50
Options Outstanding, Number Outstanding at 12/31/17	200,000
Options outstanding, Weighted Average Remaining Contractual Life (years)	4 years 3 months 19 days
Options Outstanding, Weighted Average Exercise Price	$ 2.85
Options Exercisable, Number Exercisable at 12/31/17	190,000
Options Exercisable, Weighted Average Exercise Price	$ 2.84
Stock Options [Member] \| Range two [Member]
Summary of options outstanding by exercise price range
Range of Exercise Price, Lower Range Limit	3.51
Range of Exercise Price, Upper Range Limit	$ 5.00
Options Outstanding, Number Outstanding at 12/31/17	1,426,000
Options outstanding, Weighted Average Remaining Contractual Life (years)	1 year 10 months 6 days
Options Outstanding, Weighted Average Exercise Price	$ 4.23
Options Exercisable, Number Exercisable at 12/31/17	1,426,000
Options Exercisable, Weighted Average Exercise Price	$ 4.23
Stock Options [Member] \| Range three [Member]
Summary of options outstanding by exercise price range
Range of Exercise Price, Lower Range Limit	5.01
Range of Exercise Price, Upper Range Limit	$ 6.21
Options Outstanding, Number Outstanding at 12/31/17	130,000
Options outstanding, Weighted Average Remaining Contractual Life (years)	2 years 7 months 17 days
Options Outstanding, Weighted Average Exercise Price	$ 5.98
Options Exercisable, Number Exercisable at 12/31/17	130,000
Options Exercisable, Weighted Average Exercise Price	$ 5.98