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Note 11 - Stock Based Compensation (Details) - Summary of Stock Option Awards And Changes (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Oct. 30, 2013	Dec. 31, 2012	Dec. 31, 2010
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of options outstanding (in Shares)	1,744,755	861,905	900,000	725,529	691,809
Weighted average remaining contractual term	7 years 6 months
Weighted average exercise price	$ 7.20	$ 12.29		$ 14.63	$ 16.88
Number of options exercisable (in Shares)	990,936
Weighted average remaining contractual term	6 years 36 days
Range 1 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range of exercise prices	$ 2.00
Upper range of exercise prices	$ 3.99
Number of options outstanding (in Shares)	956,700
Weighted average remaining contractual term	9 years 146 days
Weighted average exercise price	$ 3.53
Number of options exercisable (in Shares)	293,266
Weighted average remaining contractual term	9 years 146 days
Weighted average exercise price	$ 3.54
Range 2 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range of exercise prices	$ 4.00
Upper range of exercise prices	$ 8.99
Number of options outstanding (in Shares)	185,778
Weighted average remaining contractual term	7 years 219 days
Weighted average exercise price	$ 4.46
Number of options exercisable (in Shares)	131,044
Weighted average remaining contractual term	7 years 73 days
Weighted average exercise price	$ 4.41
Range 3 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range of exercise prices	$ 9.00
Upper range of exercise prices	$ 13.49
Number of options outstanding (in Shares)	434,445
Weighted average remaining contractual term	4 years 328 days
Weighted average exercise price	$ 11.12
Number of options exercisable (in Shares)	401,461
Weighted average remaining contractual term	4 years 255 days
Weighted average exercise price	$ 11.25
Range 4 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Lower range of exercise prices	$ 13.50
Upper range of exercise prices	$ 31.49
Number of options outstanding (in Shares)	165,870
Weighted average remaining contractual term	3 years 146 days
Weighted average exercise price	$ 20.81
Number of options exercisable (in Shares)	163,203
Weighted average remaining contractual term	3 years 109 days
Weighted average exercise price	$ 20.80
Range 5 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of options outstanding (in Shares)	1,962
Weighted average remaining contractual term	6 months
Weighted average exercise price	$ 38.07
Number of options exercisable (in Shares)	1,962
Weighted average remaining contractual term	6 months
Weighted average exercise price	$ 38.09