Note 2 - Acquisitions (Details) - Pro forma information - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pro forma information [Abstract]
Revenue (1)	[1]	$ 100,997	$ 95,176	$ 294,137	$ 281,174
Net income		$ 31,830	$ 8,778	$ 62,497	$ 45,973
Earnings per share (in Dollars per share)		$ 1.06	$ 0.31	$ 2.01	$ 1.63

[1] Net interest income plus noninterest income.