Note 5 - Stock-Based Compensation (Detail) - Restricted Stock Units	1 Months Ended	12 Months Ended		3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2013 Restricted Stock Units (RSUs) [Member]
Balance at December 31, 2012				256,616
Balance at March 31, 2013				208,375
Granted	14,416	125,133	147,661	14,416
Forfeited				0
Vested				(62,657)