Note 13 - Subsequent Events (Details Textual) $ / shares in Units, $ in Millions		1 Months Ended	9 Months Ended
	Oct. 11, 2016 USD ($) $ / shares shares	Oct. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jul. 11, 2005 $ / shares
Subsequent Event [Member] | Bank [Member]
Stock Issued During Period, Shares, Employee Stock Purchase Plans | shares	190,716
Subsequent Event [Member] | Ottawa Savings Bancorp, Inc. Merger [Member]
Business Combination, Ratio for Conversion of Acquiree's Outstanding Common Shares into Acquirer's Common Shares	1.1921
Subsequent Event [Member]
Increase (Decrease) in Deposits from Subscriptions Held		$ (29.5)
Proceeds from Issuance of Common Stock	$ 23.8
Stock Issued During Period, Shares, New Issues | shares	2,383,950
Share Price | $ / shares	$ 10
Increase (Decrease) in Assets from Subscriptions Held		$ (29.5)
Increase (Decrease) in Deposits from Subscriptions Held			$ 55.2
Share Price | $ / shares				$ 10
Increase (Decrease) in Assets from Subscriptions Held			62.5
Increase (Decrease) in Federal Funds Sold from Subscriptions Held			$ 54.3