Note 5 - Fair Value of Financial Instruments - Estimated Fair Value of Company's Financial Instruments (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Reported Value Measurement [Member]
Cash and cash equivalents	$ 34,594,000	$ 39,782,000
Total	80,116,000	111,974,000
Loans held for sale	5,879,000	3,779,000
Loans receivable, net	540,583,000	458,539,000
Federal Home Loan Bank stock	770,000	691,000
Accrued interest receivable	2,235,000	2,254,000
Deposits	592,243,000	558,731,000
Other borrowings	9,000,000	9,000,000
Accrued interest payable	238,000	242,000
Commitments to extend credit	167,000	36,000
Commitments to sell loans	(138,000)	(26,000)
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	34,594,000
Total		111,974,000
Loans held for sale		3,779,000
Loans receivable, net		458,539,000
Federal Home Loan Bank stock		691,000
Accrued interest receivable		2,254,000
Deposits		558,731,000
Other borrowings		9,000,000
Accrued interest payable		242,000
Commitments to extend credit
Commitments to sell loans
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Total	80,116,000
Loans held for sale	5,879,000
Loans receivable, net	542,779,000
Federal Home Loan Bank stock	770,000
Accrued interest receivable	2,235,000
Deposits	592,565,000
Other borrowings	9,010,000
Accrued interest payable	238,000
Commitments to extend credit		165,949,000
Commitments to sell loans		8,071,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Total
Loans held for sale
Loans receivable, net
Federal Home Loan Bank stock
Accrued interest receivable
Deposits
Other borrowings
Accrued interest payable
Commitments to extend credit	237,879,000
Commitments to sell loans	18,251,000
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	34,594,000	39,782,000
Total	80,116,000
Loans held for sale	5,879,000
Loans receivable, net	542,779,000
Federal Home Loan Bank stock	770,000
Accrued interest receivable	2,235,000
Deposits	592,565,000
Other borrowings	9,010,000
Accrued interest payable	238,000
Commitments to extend credit	167,000
Commitments to sell loans	(138,000)
Portion at Other than Fair Value Measurement [Member]
Cash and cash equivalents	39,782,000
Total	111,974,000
Loans held for sale	3,779,000
Loans receivable, net	463,185,000
Federal Home Loan Bank stock	691,000
Accrued interest receivable	2,254,000
Deposits	559,387,000
Other borrowings	9,000,000
Accrued interest payable	242,000
Commitments to extend credit	36,000
Commitments to sell loans	(26,000)
Total	$ 80,116,000	$ 111,974,000