Note 12 - Stock Plans (Details) - Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range (USD $)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options Outstanding	109,871
Weighted-Average Remaining Contractual Life (in years)	4 years 219 days
Number of Options Exercisable	53,186
Exercise Price 1 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 2.88
Number of Options Outstanding	2,655
Weighted-Average Remaining Contractual Life (in years)	3 years 255 days
Exercise Price 2 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 4.18
Number of Options Outstanding	1,240
Weighted-Average Remaining Contractual Life (in years)	3 years 255 days
Exercise Price 3 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 4.83
Number of Options Outstanding	42,910
Weighted-Average Remaining Contractual Life (in years)	9 years 36 days
Exercise Price 4 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 6.91
Number of Options Outstanding	623
Weighted-Average Remaining Contractual Life (in years)	3 years 255 days
Exercise Price 5 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 8.94
Number of Options Outstanding	6,211
Weighted-Average Remaining Contractual Life (in years)	3 years 36 days
Exercise Price 6 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 9.03
Number of Options Outstanding	3,653
Weighted-Average Remaining Contractual Life (in years)	2 years 73 days
Exercise Price 7 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 11.19
Number of Options Outstanding	5,715
Weighted-Average Remaining Contractual Life (in years)	292 days
Exercise Price 8 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 12.11
Number of Options Outstanding	7,041
Weighted-Average Remaining Contractual Life (in years)	2 years 73 days
Exercise Price 9 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 12.20
Number of Options Outstanding	4,745
Weighted-Average Remaining Contractual Life (in years)	2 years 73 days
Exercise Price 10 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 12.21
Number of Options Outstanding	4,638
Weighted-Average Remaining Contractual Life (in years)	1 year 109 days
Exercise Price 11 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 12.52
Number of Options Outstanding	6,483
Weighted-Average Remaining Contractual Life (in years)	2 years 73 days
Exercise Price 12 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 13.61
Number of Options Outstanding	2,999
Weighted-Average Remaining Contractual Life (in years)	1 year 109 days
Exercise Price 13 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 13.88
Number of Options Outstanding	4,493
Weighted-Average Remaining Contractual Life (in years)	292 days
Exercise Price 14 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 14.18
Number of Options Outstanding	3,351
Weighted-Average Remaining Contractual Life (in years)	292 days
Exercise Price 15 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 14.50
Number of Options Outstanding	4,172
Weighted-Average Remaining Contractual Life (in years)	292 days
Exercise Price 16 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 16.49
Number of Options Outstanding	2,653
Weighted-Average Remaining Contractual Life (in years)	1 year 109 days
Exercise Price 17 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 18.58
Number of Options Outstanding	2,889
Weighted-Average Remaining Contractual Life (in years)	1 year 109 days
Exercise Price 18 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 22.54
Number of Options Outstanding	3,400
Weighted-Average Remaining Contractual Life (in years)	109 days
Exercise Price 19 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price	$ 30.22
Weighted-Average Remaining Contractual Life (in years)	0 years