Note 1 - Business Description (Details Textual) $ / shares in Units, $ in Thousands		102 Months Ended
	Jul. 31, 2017 $ / shares shares	Jan. 10, 2020	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Assets, Total			$ 4,228,194	$ 3,350,072
Loans Held for Investment and Held for Sale, Gross			2,900,000
Deposits, Total			3,385,532	2,635,128
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance			$ 466,683	$ 428,488	$ 407,690	$ 374,621
Number of Businesses Acquired		6
PGB Holdings Inc. [Member]
Number of Branches		3
PGB Holdings Inc. [Member] | ILLINOIS
Number of Branches		3
IPO [Member]
Stock Issued During Period, Shares, New Issues (in shares) | shares	3,750,000
Share Price (in dollars per share) | $ / shares	$ 23.00