Note 5 - Loans Receivable - Loans Restructured as TDRs (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2016 USD ($)	Dec. 31, 2015	Dec. 31, 2014 USD ($)
Number of Loans		4	0	3
Balance prior to TDR		$ 4,572		$ 199
Balance		4,534		189
Modification of Payment Terms [Member]
Balance	[1]	$ 4,572		114
Other Modifications [Member]
Balance	[2]			$ 85
Real Estate Portfolio Segment [Member] | One-to-Four-Family Residential [Member]
Number of Loans		1		1
Balance prior to TDR		$ 5		$ 103
Balance		2		95
Real Estate Portfolio Segment [Member] | One-to-Four-Family Residential [Member] | Modification of Payment Terms [Member]
Balance	[1]	$ 5		103
Real Estate Portfolio Segment [Member] | One-to-Four-Family Residential [Member] | Other Modifications [Member]
Balance	[2]			$ 0
Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member]
Number of Loans		1
Balance prior to TDR		$ 4,244
Balance		4,244
Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member] | Modification of Payment Terms [Member]
Balance	[1]	$ 4,244
Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Number of Loans				1
Balance prior to TDR				$ 85
Balance				84
Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Modification of Payment Terms [Member]
Balance	[1]			0
Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Other Modifications [Member]
Balance	[2]			$ 85
Commercial Portfolio Segment [Member]
Number of Loans		2
Balance prior to TDR		$ 323
Balance		288
Commercial Portfolio Segment [Member] | Modification of Payment Terms [Member]
Balance	[1]	$ 323
Consumer Portfolio Segment [Member]
Number of Loans				1
Balance prior to TDR				$ 11
Balance				10
Consumer Portfolio Segment [Member] | Modification of Payment Terms [Member]
Balance	[1]			11
Consumer Portfolio Segment [Member] | Other Modifications [Member]
Balance	[2]			$ 0

[1] Concessions represent skipped payments/maturity date extensions, amortization term extensions or conversion from amortizing terms to interest only.

[2] The borrower did not have the financial ability to refinance at another bank at renewal.