Note 16 - Stock-based Compensation - Summary of Information About Stock-based Awards Outstanding (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Exercise Price (in dollars per share)		$ 2,438
Number of Shares Outstanding (in shares)	4,100	3,300
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	51959 years	27148 years
Aggregate Intrinsic Value, Options Outstanding	$ 557	$ 857
Number of Shares Exercisable (in shares)	2,700	2,400
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	15827 years	8526 years
Exercise Price 1 [Member]
Exercise Price (in dollars per share)	$ 15	$ 15
Number of Shares Outstanding (in shares)	2,800	3,800
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	526 years	269 years
Aggregate Intrinsic Value, Options Outstanding	$ 15	$ 15
Number of Shares Exercisable (in shares)	2,800	3,800
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	526 years	269 years
Exercise Price 2 [Member]
Exercise Price (in dollars per share)	$ 15	$ 15
Number of Shares Outstanding (in shares)	2,600	3,600
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	509 years	252 years
Aggregate Intrinsic Value, Options Outstanding	$ 15	$ 15
Number of Shares Exercisable (in shares)	2,600	3,600
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	509 years	252 years
Exercise Price 3 [Member]
Exercise Price (in dollars per share)	$ 108	$ 326
Number of Shares Outstanding (in shares)	2,300	3,300
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	3608 years	5327 years
Aggregate Intrinsic Value, Options Outstanding	$ 108	$ 69
Number of Shares Exercisable (in shares)	2,300	3,300
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	3608 years	1135 years
Exercise Price 4 [Member]
Exercise Price (in dollars per share)	$ 53	$ 100
Number of Shares Outstanding (in shares)	2,300	3,300
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	1761 years	1593 years
Aggregate Intrinsic Value, Options Outstanding	$ 28	$ 50
Number of Shares Exercisable (in shares)	2,300	3,300
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	934 years	797 years
Exercise Price 5 [Member]
Exercise Price (in dollars per share)	$ 635	$ 938
Number of Shares Outstanding (in shares)	2,400	3,400
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	19226 years	12315 years
Aggregate Intrinsic Value, Options Outstanding	$ 140	$ 126
Number of Shares Exercisable (in shares)	2,400	3,400
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	4247 years	1655 years
Exercise Price 6 [Member]
Exercise Price (in dollars per share)	$ 9	$ 33
Number of Shares Outstanding (in shares)	2,100	3,100
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	269 years	387 years
Aggregate Intrinsic Value, Options Outstanding	$ 1	$ 16
Number of Shares Exercisable (in shares)	2,100	3,100
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	33 years	193 years
Exercise Price 7 [Member]
Exercise Price (in dollars per share)	$ 68	$ 135
Number of Shares Outstanding (in shares)	1,300	2,300
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	1905 years	1462 years
Aggregate Intrinsic Value, Options Outstanding	$ 68	$ 135
Number of Shares Exercisable (in shares)	1,300	2,300
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	1905 years	1462 years
Exercise Price 8 [Member]
Exercise Price (in dollars per share)	$ 15	$ 45
Number of Shares Outstanding (in shares)	3,800	4,800
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	404 years	440 years
Aggregate Intrinsic Value, Options Outstanding	$ 15	$ 45
Number of Shares Exercisable (in shares)	3,800	4,800
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	404 years	440 years
Exercise Price 9 [Member]
Exercise Price (in dollars per share)	$ 30	$ 64
Number of Shares Outstanding (in shares)	4,800	200
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	762 years	618 years
Aggregate Intrinsic Value, Options Outstanding	$ 30	$ 64
Number of Shares Exercisable (in shares)	4,800	200
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	762 years	618 years
Exercise Price 10 [Member]
Exercise Price (in dollars per share)	$ 400	$ 15
Number of Shares Outstanding (in shares)	3,600	1,800
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	9640 years	124 years
Aggregate Intrinsic Value, Options Outstanding	$ 75	$ 15
Number of Shares Exercisable (in shares)	3,600	1,800
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	1807 years	124 years
Exercise Price 11 [Member]
Exercise Price (in dollars per share)	$ 17	$ 45
Number of Shares Outstanding (in shares)	300	5,800
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	400 years	371 years
Aggregate Intrinsic Value, Options Outstanding	$ 17	$ 45
Number of Shares Exercisable (in shares)	300	5,800
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	400 years	371 years
Exercise Price 12 [Member]
Exercise Price (in dollars per share)	$ 15	$ 3
Number of Shares Outstanding (in shares)	6,100	1,300
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	277 years	22 years
Aggregate Intrinsic Value, Options Outstanding		$ 3
Number of Shares Exercisable (in shares)		1,300
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)		22 years
Exercise Price 13 [Member]
Exercise Price (in dollars per share)	$ 45	$ 400
Number of Shares Outstanding (in shares)	5,800	4,600
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	692 years	2780 years
Aggregate Intrinsic Value, Options Outstanding	$ 45
Number of Shares Exercisable (in shares)	5,800
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)	692 years
Exercise Price 14 [Member]
Exercise Price (in dollars per share)	$ 1,080	$ 148
Number of Shares Outstanding (in shares)	5,500	1,300
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	11610 years	963 years
Aggregate Intrinsic Value, Options Outstanding		$ 148
Number of Shares Exercisable (in shares)		1,300
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)		963 years
Exercise Price 15 [Member]
Exercise Price (in dollars per share)	$ 60	$ 96
Number of Shares Outstanding (in shares)	6,900	300
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)	370 years	225 years
Aggregate Intrinsic Value, Options Outstanding		$ 96
Number of Shares Exercisable (in shares)		300
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)		225 years
Exercise Price 16 [Member]
Exercise Price (in dollars per share)		$ 15
Number of Shares Outstanding (in shares)		6,800
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)
Aggregate Intrinsic Value, Options Outstanding
Number of Shares Exercisable (in shares)
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)
Exercise Price 17 [Member]
Exercise Price (in dollars per share)		$ 15
Number of Shares Outstanding (in shares)		800
Weighted Average Remaining Contractual Life in Years, Options Outstanding (Year)
Aggregate Intrinsic Value, Options Outstanding		$ 15
Number of Shares Exercisable (in shares)		800
Weighted Average Remaining Contractual Life in Years, Options Exercisable (Year)