Note 9 - Allowance for Loan Losses and Credit Quality Information - Classified and Unclassified Loans (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Classified [Member] | Special Mention [Member] | One to Four Family Porfolio Segment [Member]
Loans and leases receivable, gross carrying amount	$ 524,000	$ 189,000
Classified [Member] | Special Mention [Member] | Commercial Portfolio Segment [Member] | Commercial Business Other [Member]
Loans and leases receivable, gross carrying amount	2,412,000	841,000
Classified [Member] | Special Mention [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	1,986,000	917,000
Classified [Member] | Special Mention [Member] | Consumer Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Special Mention [Member]
Loans and leases receivable, gross carrying amount	4,922,000	7,939,000
Classified [Member] | Substandard [Member] | One to Four Family Porfolio Segment [Member]
Loans and leases receivable, gross carrying amount	2,367,000	2,889,000
Classified [Member] | Substandard [Member] | Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	7,189,000	4,827,000
Classified [Member] | Substandard [Member] | Commercial Portfolio Segment [Member] | Transportation Industry Loans [Member]
Loans and leases receivable, gross carrying amount	3,884,000	18,000
Classified [Member] | Substandard [Member] | Commercial Portfolio Segment [Member] | Commercial Business Other [Member]
Loans and leases receivable, gross carrying amount	1,385,000	1,515,000
Classified [Member] | Substandard [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	8,995,000	9,473,000
Classified [Member] | Substandard [Member] | Consumer Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	816,000	639,000
Classified [Member] | Substandard [Member]
Loans and leases receivable, gross carrying amount	24,636,000	19,361,000
Classified [Member] | Doubtful [Member] | One to Four Family Porfolio Segment [Member]
Loans and leases receivable, gross carrying amount	50,000	55,000
Classified [Member] | Doubtful [Member] | Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Doubtful [Member] | Commercial Portfolio Segment [Member] | Transportation Industry Loans [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Doubtful [Member] | Commercial Portfolio Segment [Member] | Commercial Business Other [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Doubtful [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Doubtful [Member] | Consumer Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	50,000	52,000
Classified [Member] | Doubtful [Member]
Loans and leases receivable, gross carrying amount	100,000	107,000
Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | One to Four Family Porfolio Segment [Member]
Loans and leases receivable, gross carrying amount	67,000	0
Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Portfolio Segment [Member] | Transportation Industry Loans [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Portfolio Segment [Member] | Commercial Business Other [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	0	0
Classified [Member] | Unlikely to be Collected Financing Receivable [Member] | Consumer Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	269,000	286,000
Classified [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans and leases receivable, gross carrying amount	336,000	286,000
Classified [Member] | Internal Investment Grade [Member] | Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	0	1,910,000
Classified [Member] | Internal Investment Grade [Member] | Commercial Portfolio Segment [Member] | Transportation Industry Loans [Member]
Loans and leases receivable, gross carrying amount	0	4,082,000
Classified [Member] | One to Four Family Porfolio Segment [Member]
Loans and leases receivable, gross carrying amount	3,008,000	3,133,000
Classified [Member] | Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	7,189,000	6,737,000
Classified [Member] | Commercial Portfolio Segment [Member] | Transportation Industry Loans [Member]
Loans and leases receivable, gross carrying amount	3,884,000	4,100,000
Classified [Member] | Commercial Portfolio Segment [Member] | Commercial Business Other [Member]
Loans and leases receivable, gross carrying amount	3,797,000	2,356,000
Classified [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	10,981,000	10,390,000
Classified [Member] | Consumer Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	1,135,000	977,000
Classified [Member]
Loans and leases receivable, gross carrying amount	29,994,000	27,693,000
Unclassified [Member] | One to Four Family Porfolio Segment [Member]
Loans and leases receivable, gross carrying amount	97,712,000	87,812,000
Unclassified [Member] | Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	151,250,000	118,639,000
Unclassified [Member] | Commercial Portfolio Segment [Member] | Transportation Industry Loans [Member]
Loans and leases receivable, gross carrying amount	6,619,000	5,249,000
Unclassified [Member] | Commercial Portfolio Segment [Member] | Commercial Business Other [Member]
Loans and leases receivable, gross carrying amount	59,233,000	58,401,000
Unclassified [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	122,330,000	111,587,000
Unclassified [Member] | Consumer Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	73,327,000	63,438,000
Unclassified [Member]
Loans and leases receivable, gross carrying amount	510,471,000	445,126,000
One to Four Family Porfolio Segment [Member]
Loans and leases receivable, gross carrying amount	100,720,000	90,945,000
Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	158,439,000	125,376,000
Commercial Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	133,311,000	121,977,000
Commercial Portfolio Segment [Member] | Transportation Industry Loans [Member]
Loans and leases receivable, gross carrying amount	10,503,000	9,349,000
Commercial Portfolio Segment [Member] | Commercial Business Other [Member]
Loans and leases receivable, gross carrying amount	63,030,000	60,757,000
Commercial Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	73,533,000	70,106,000
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Loans and leases receivable, gross carrying amount	158,439,000	125,376,000
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Loans and leases receivable, gross carrying amount	133,311,000	121,977,000
Commercial Real Estate Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	291,750,000	247,353,000
Consumer Portfolio Segment [Member]
Loans and leases receivable, gross carrying amount	74,462,000	64,415,000
Loans and leases receivable, gross carrying amount	$ 540,465,000	$ 472,819,000