Note 2 - Sales/Mergers/Acquisitions - Sale of Rockford Bank & Trust (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Nov. 30, 2019	Nov. 30, 2019	Dec. 31, 2019
ASSETS
Total assets sold			$ 11,966
LIABILITIES
Total liabilities sold			5,003
Gain on sale of certain assets and certain liabilities of RB&T:			12,286
Assets held for sale			11,966
Liabilities held for sale			5,003
Disposition costs			3,325
RB&T
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Purchase price premium for intangible assets	8.00%
Purchase price premium multiplied	0.345
Purchase price premium	$ 12,500
ASSETS
Cash and cash equivalents	3,973	$ 3,973	3,973
Interest-bearing deposits at financial institutions	55,291	55,291	55,291
Securities held to maturity, at amortized cost	3,243	3,243	3,243
Securities available for sale, at fair value	21,874	21,874	21,874
Loans/leases receivable held for investment, net	357,931	357,931	357,931
Premises and equipment, net	5,612	5,612	5,612
Restricted investment securities	675	675	675
Other real estate owned, net	2,134	2,134	2,134
Other assets	3,228	3,228	3,228
Total assets sold	453,961	453,961	453,961
LIABILITIES
Noninterest-bearing deposits	69,802	69,802	69,802
Interest-bearing deposits	331,486	331,486	331,486
Short-term borrowings	1,158	1,158	1,158
Federal Home Loan Bank advances	15,000	15,000	15,000
Other liabilities	2,241	2,241	2,241
Total liabilities sold	419,687	419,687	419,687
Net assets sold	34,274	34,274
Cash consideration received	46,560	46,560	46,560
Gain on sale of certain assets and certain liabilities of RB&T:		12,286	12,286
Assets held for sale	453,961	453,961	453,961
Liabilities held for sale	$ 419,687	$ 419,687	419,687
Asset held-for-sale
ASSETS
Total assets sold			12,000
LIABILITIES
Total liabilities sold			5,000
Assets held for sale			12,000
Liabilities held for sale			5,000
Disposition costs			$ 3,300