Note 8 - Stock Options and Stock-based Employee Compensation (Tables)

9 Months Ended

Sep. 30, 2016

Notes Tables

Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block]

(in thousands, except for weighted-average data)
Stock Options	Shares			Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (In Yrs)
Outstanding at December 31, 2015		517		$	51.35
Granted		763			2.09
Forfeited or expired		(138	)		69.15
Outstanding at September 30, 2016		1,142		$	16.30		8.2
Vested and exercisable at September 30, 2016		303		$	49.97		5.2

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Nine Months Ended
	September 30,
	2016			2015
Weighted average expected volatility		78	%		83	%
Weighted average expected term (years)		5.7			5.6
Weighted average risk-free interest rate		1.4	%		1.5	%
Expected dividends		–			–

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three Months Ended				Nine Months Ended
(in thousands)	September 30,				September 30,
	2016		2015		2016		2015
Research and development	$	140	$	192	$	462	$	551
Selling, general and administrative		133		226		664		801
Total	$	273	$	418	$	1,126	$	1,352