Note 3 - Loans Receivable - Impaired Loans, Average Recorded Investment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Average recorded investment	$ 748	$ 1,851
Residential Portfolio Segment [Member] | One-to-Four Family Loans [Member]
Average recorded investment	221	668
Commercial Real Estate Portfolio Segment [Member]
Average recorded investment		662
Real Estate Construction Portfolio Segment [Member]
Average recorded investment
Home Equity Portfolio Segment [Member]
Average recorded investment	338	236
Consumer Portfolio Segment [Member]
Average recorded investment	116	119
Commercial Portfolio Segment [Member]
Average recorded investment	$ 73	$ 166