Note 13 - Income Taxes (Details) - Reconciliation of Income Taxes (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Income Taxes [Abstract]
Income tax benefit using U.S. federal statutory rate	$ (1,136)	$ (2,690)	$ (2,710)
Permanent differences	124	299	38
Orphan drug credit permanent addback	674
State income taxes, net of federal benefit	(303)	(389)	(368)
Tax credits	(2,176)	(7,164)	(95)
Expiring net operating losses and tax credits	312	2,566	287
Change in valuation allowance	4,394	7,286	2,988
Mark to market derivative liability	(1,779)
Other	$ (110)us-gaap_IncomeTaxExpenseBenefit	$ 92us-gaap_IncomeTaxExpenseBenefit	$ (140)us-gaap_IncomeTaxExpenseBenefit

Represents the difference resulting from mark to market valuation for derivative liabilities.

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- Definition

Represents state income taxes net of federal benefit.

+ References

No definition available.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

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- Definition

The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Number 210

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-Paragraph h

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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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