Note 6 - Loans and the Allowance for Loan Losses - Summary of Allowance for Credit Losses and Recorded Investment in Loans Receivable (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Allowance for credit losses, Individually evaluated for impairment		$ 1,032		$ 1,032		$ 887
Allowance for credit losses, Collectively evaluated for impairment		8,111		8,111		7,242
Allowance for credit losses, Purchased Credit Impaired	[1]	34		34		33
Loans receivable, Ending Balance		874,506		874,506		810,951
Loans receivable, Individually evaluated for impairment		11,260		11,260		12,009
Loans receivable, Collectively evaluated for impairment		862,497		862,497		797,166
Loans receivable, Purchased Credit Impaired	[1]	749		749		1,776
Beginning Balance				8,162	$ 7,244	7,244
Charge-offs				(722)		(1,789)
Recoveries				77		1,487
Provision		1,305	$ 150	1,660	820	1,220
Ending Balance		9,177		9,177		8,162
Commercial Real Estate Portfolio Segment [Member] | Construction and Land [Member]
Allowance for credit losses, Individually evaluated for impairment		22		22		0
Allowance for credit losses, Collectively evaluated for impairment		1,165		1,165		933
Allowance for credit losses, Purchased Credit Impaired	[1]	0		0		0
Loans receivable, Ending Balance		112,199		112,199		94,426
Loans receivable, Individually evaluated for impairment		133		133		143
Loans receivable, Collectively evaluated for impairment		112,053		112,053		94,117
Loans receivable, Purchased Credit Impaired	[1]	13		13		166
Beginning Balance				933	600	600
Charge-offs				(2)		(484)
Recoveries				1		10
Provision				255		807
Ending Balance		1,187		1,187		933
Commercial Real Estate Portfolio Segment [Member] | Farmland [Member]
Allowance for credit losses, Individually evaluated for impairment		0		0		0
Allowance for credit losses, Collectively evaluated for impairment		88		88		75
Allowance for credit losses, Purchased Credit Impaired	[1]	0		0		0
Loans receivable, Ending Balance		10,524		10,524		9,217
Loans receivable, Individually evaluated for impairment		0		0		0
Loans receivable, Collectively evaluated for impairment		10,524		10,524		9,217
Loans receivable, Purchased Credit Impaired	[1]	0		0		0
Beginning Balance				75	30	30
Charge-offs				0		0
Recoveries				0		0
Provision				13		45
Ending Balance		88		88		75
Commercial Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member]
Allowance for credit losses, Individually evaluated for impairment		112		112		98
Allowance for credit losses, Collectively evaluated for impairment		2,331		2,331		2,216
Allowance for credit losses, Purchased Credit Impaired	[1]	0		0		0
Loans receivable, Ending Balance		304,278		304,278		298,057
Loans receivable, Individually evaluated for impairment		3,049		3,049		1,073
Loans receivable, Collectively evaluated for impairment		300,705		300,705		295,590
Loans receivable, Purchased Credit Impaired	[1]	524		524		1,394
Beginning Balance				2,314	1,416	1,416
Charge-offs				(617)		(473)
Recoveries				1		1,258
Provision				745		113
Ending Balance		2,443		2,443		2,314
Residential Portfolio Segment [Member] | Real Estate Residential One- to Four-Family [Member]
Allowance for credit losses, Individually evaluated for impairment		416		416		252
Allowance for credit losses, Collectively evaluated for impairment		1,092		1,092		943
Allowance for credit losses, Purchased Credit Impaired	[1]	34		34		33
Loans receivable, Ending Balance		139,398		139,398		129,052
Loans receivable, Individually evaluated for impairment		2,916		2,916		3,263
Loans receivable, Collectively evaluated for impairment		136,270		136,270		125,573
Loans receivable, Purchased Credit Impaired	[1]	212		212		216
Beginning Balance				1,228	1,021	1,021
Charge-offs				(20)		(162)
Recoveries				14		140
Provision				320		229
Ending Balance		1,542		1,542		1,228
Residential Portfolio Segment [Member] | Multi-family Residential [Member]
Allowance for credit losses, Individually evaluated for impairment		0		0		0
Allowance for credit losses, Collectively evaluated for impairment		185		185		172
Allowance for credit losses, Purchased Credit Impaired	[1]	0		0		0
Loans receivable, Ending Balance		23,039		23,039		22,737
Loans receivable, Individually evaluated for impairment		0		0		0
Loans receivable, Collectively evaluated for impairment		23,039		23,039		22,737
Loans receivable, Purchased Credit Impaired	[1]	0		0		0
Beginning Balance				172	101	101
Charge-offs				0		0
Recoveries				0		0
Provision				13		71
Ending Balance		185		185		172
Commercial Portfolio Segment [Member]
Allowance for credit losses, Individually evaluated for impairment		482		482		501
Allowance for credit losses, Collectively evaluated for impairment		2,860		2,860		2,538
Allowance for credit losses, Purchased Credit Impaired	[1]	0		0		0
Loans receivable, Ending Balance		238,924		238,924		213,120
Loans receivable, Individually evaluated for impairment		4,927		4,927		7,332
Loans receivable, Collectively evaluated for impairment		233,997		233,997		205,788
Loans receivable, Purchased Credit Impaired	[1]	0		0		0
Beginning Balance				3,039	3,618	3,618
Charge-offs				(53)		(667)
Recoveries				30		33
Provision				326		55
Ending Balance		3,342		3,342		3,039
Consumer Portfolio Segment [Member]
Allowance for credit losses, Individually evaluated for impairment		0		0		36
Allowance for credit losses, Collectively evaluated for impairment		390		390		365
Allowance for credit losses, Purchased Credit Impaired	[1]	0		0		0
Loans receivable, Ending Balance		46,144		46,144		44,342
Loans receivable, Individually evaluated for impairment		235		235		198
Loans receivable, Collectively evaluated for impairment		45,909		45,909		44,144
Loans receivable, Purchased Credit Impaired	[1]	0		0		0
Beginning Balance				401	$ 458	458
Charge-offs				(30)		(3)
Recoveries				31		46
Provision				(12)		(100)
Ending Balance		$ 390		$ 390		$ 401

[1] Purchased credit impaired loans are evaluated for impairment on an individual basis.