Note 2 - Acquisitions - Summary of Unaudited Pro forma Information (Details) - Liberty and Community First [Member] - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Revenue (1)	[1]	$ 395,959	$ 390,606
Net income		$ 85,773	$ 64,166
Earnings per share (in dollars per share)		$ 2.68	$ 2.24

[1] Net interest income plus noninterest income.