Note 5 - Loans Receivable - Purchased Credit Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Jun. 13, 2014
PCI Loans	$ 6,220	$ 12,384	$ 21,105
PCI Loans	8,529	15,468	26,942
Real Estate Portfolio Segment [Member] | One-to-Four-Family Residential [Member]
PCI Loans	2,210	2,714	4,728
Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member]
PCI Loans	1,987	7,576	10,790
Real Estate Portfolio Segment [Member] | Farmland [Member]
PCI Loans	26	53	95
Real Estate Portfolio Segment [Member] | Construction Loans [Member]
PCI Loans	1,442	1,432	3,432
Commercial Portfolio Segment [Member]
PCI Loans	514	556	1,882
Consumer Portfolio Segment [Member]
PCI Loans	$ 41	$ 53	$ 178