Note 3 - Summary of Significant Accounting Policies (Details) - Basic and Diluted Earnings Per Share (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Basic and Diluted Earnings Per Share [Abstract]
Net income (in Dollars)	$ 12,106	$ 11,452	$ 27,750	$ 36,484
Weighted average shares outstanding used in calculating basic earnings per share	13,771	14,661	14,299	14,648
Dilutive common share equivalents	112	251	94	178
Weighted average common and common share equivalents used in calculating diluted earnings per share	13,883	14,912	14,393	14,826
Basic (in Dollars per share)	$ 0.88	$ 0.78	$ 1.94	$ 2.49
Diluted (in Dollars per share)	$ 0.87	$ 0.77	$ 1.93	$ 2.46
Options and restricted share units outstanding which are not included in the calculation of diluted earnings per share because their impact is anti-dilutive	123		78	3