Note 12 - Earn-out Milestone Liability (Details Textual) - USD ($)		1 Months Ended	12 Months Ended
Jun. 30, 2015	Jun. 20, 2014	Dec. 31, 2016	Dec. 31, 2015
Gain (Loss) from Change in Fair Value of Earn out Milestone Liability			$ (733,186)	$ 257,702
EGEN Inc [Member]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		$ 30,400,000	30,400,000
Business Combination, Consideration Transferred, Liabilities Incurred	$ 13,700,000	$ 13,900,000	13,200,000	13,900,000
Gain (Loss) from Change in Fair Value of Earn out Milestone Liability			$ 700,000	$ 257,702
EGEN Inc [Member] \| Minimum [Member]
Risk Adjusted Assessment of Each Milestone		10.00%	50.00%	10.00%
Estimated Time to Achieve the Milestone		1 year 182 days	2 years	1 year 73 days
EGEN Inc [Member] \| Maximum [Member]
Risk Adjusted Assessment of Each Milestone		67.00%	80.00%	67.00%
Estimated Time to Achieve the Milestone		2 years 182 days	2 years 182 days	6 years 182 days

The amount of estimated time to achieve the milestone.

No definition available.

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- Definition

The amount of gain (loss) from the change in the fair value of earn-out milestone liability.

+ References

No definition available.

+ Details

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- Definition

The percentage of risk-adjusted assessment of each milestone.

+ References

No definition available.

+ Details

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

+ Details

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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