Note 2 - Earnings Per Share (Details) - Earnings Per Share Computation (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Earnings Per Share Computation [Abstract]
Net income (in Dollars)	$ 6,576	$ 6,536	$ 12,513	$ 12,891	$ 14,793
Average common shares outstanding	16,415	17,044	16,465	17,130
Average potential dilutive common shares	3	5	4	4
Average diluted common shares	16,418	17,049	16,469	17,134
Basic earnings per share (in Dollars per share)	$ 0.40	$ 0.38	$ 0.76	$ 0.75
Diluted earnings per share (in Dollars per share)	$ 0.40	$ 0.38	$ 0.76	$ 0.75