Note 10 - Commitments and Contingencies (Details Textual) - USD ($)		12 Months Ended
Sep. 27, 2016	Dec. 31, 2016	Dec. 31, 2015
Litigation Settlement, Expense		$ 2,500,000	$ 0
2016 Convertible Notes [Member]
Debt Instrument, Convertible, Conversion Price		$ 3.50
Settlement Agreement [Member] \| 2016 Convertible Notes [Member]
Debt Instrument, Face Amount	$ 1,900,000
Debt Instrument, Convertible, Conversion Price	$ 3.50
Litigation Settlement, Expense	$ 2,500,000
Charlottesville, Virginia [Member] \| Building [Member]
Operating Leases, Rent Expense, Net		$ 66,000	$ 66,000

The price per share of the conversion feature embedded in the debt instrument.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

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