Note 21 - Disclosures About Fair Value of Financial Instruments - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financial assets:
Securities available for sale, at fair value	$ 255,844	$ 186,751
Securities held to maturity, fair value	2	4
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	45,835	109,174
Interest-bearing time deposits	14,735	16,655
Securities available for sale, at fair value	255,844	186,751
Securities held to maturity, fair value	2	4
Loans held for sale	4,507	3,081
Loans, net	381,154	359,166
FHLB and other stock	1,650	1,650
Accrued interest receivable	2,363	2,244
FHLB and other stock	1,650	1,650
Cost method investment (included in other assets)		711
Financial liabilities:
Deposits	664,650	637,177
Accrued interest payable	133	167
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and cash equivalents	45,835	109,174
Interest-bearing time deposits	14,786	16,696
Securities available for sale, at fair value	255,844	186,751
Securities held to maturity, fair value	2	4
Loans held for sale	4,598	3,145
Loans, net	381,459	359,784
FHLB and other stock	1,650	1,650
Accrued interest receivable	2,363	2,244
FHLB and other stock	1,650	1,650
Cost method investment (included in other assets)		711
Financial liabilities:
Deposits	663,806	636,406
Accrued interest payable	133	167
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	45,835	109,174
Interest-bearing time deposits	0	0
Securities available for sale, at fair value	74	118
Securities held to maturity, fair value	0	0
Loans held for sale	0	0
Loans, net	0	0
FHLB and other stock	0	0
Accrued interest receivable	0	0
FHLB and other stock	0	0
Cost method investment (included in other assets)		0
Financial liabilities:
Deposits	0	0
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Financial assets:
Cash and cash equivalents	0	0
Interest-bearing time deposits	14,786	16,696
Securities available for sale, at fair value	255,770	186,633
Securities held to maturity, fair value	2	4
Loans held for sale	4,598	3,145
Loans, net	0	0
FHLB and other stock	1,650	1,650
Accrued interest receivable	2,363	2,244
FHLB and other stock	1,650	1,650
Cost method investment (included in other assets)		711
Financial liabilities:
Deposits	0	0
Accrued interest payable	133	167
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Financial assets:
Cash and cash equivalents	0	0
Interest-bearing time deposits	0	0
Securities available for sale, at fair value	0	0
Securities held to maturity, fair value	0	0
Loans held for sale	0	0
Loans, net	381,459	359,784
FHLB and other stock	0	0
Accrued interest receivable	0	0
FHLB and other stock	0	0
Cost method investment (included in other assets)		0
Financial liabilities:
Deposits	663,806	636,406
Accrued interest payable	$ 0	$ 0