Note 8 - Stock-Based Compensation (Details) - Stock options exercised: (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Stock options exercised: [Abstract]
Proceeds from stock options exercised	$ 77	$ 21	$ 312	$ 836
Fair value of shares received upon exercised of stock options	2,323	287	4,074	835
Tax (expense) benefit related to stock options exercised	(71)	3	97	30
Intrinsic value of stock options exercised	$ 436	$ 56	$ 813	$ 186