Note 5 - Tax Short-fall from Share-based Payment Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Tax benefit/(short-fall) of tax deductions in excess of grant-date fair value	$ (68)	$ (1,224)	$ (3,366)	$ (5,619)
Benefit of tax deductions on grant-date fair value	68	1,554	3,370	6,146
Total benefit/(short-fall) of tax deductions		$ 330	$ 4	$ 527