Note 6 - Loans Receivable and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
With no related allowance - Recorded investment	$ 21,360	$ 15,270
With no related allowance - Unpaid principal balance	26,544	19,666
With related allowance - Recorded investment	3,424	9,446
With related allowance - Unpaid principal balance	3,574	9,502
Related allowance	891	2,790
Recorded investment	24,784	24,716
Unpaid principal balance	30,118	29,168
Commercial Real Estate Portfolio Segment [Member]
With no related allowance - Recorded investment	13,811	9,264
With no related allowance - Unpaid principal balance	14,699	9,268
With related allowance - Recorded investment		6,151
With related allowance - Unpaid principal balance		6,165
Related allowance		1,964
Recorded investment	13,811	15,415
Unpaid principal balance	14,699	15,433
Construction and Land Development Portfolio Segment [Member]
With no related allowance - Recorded investment
With no related allowance - Unpaid principal balance
With related allowance - Recorded investment
With related allowance - Unpaid principal balance
Related allowance
Recorded investment
Unpaid principal balance
Commercial Portfolio Segment [Member]
With no related allowance - Recorded investment	4,818	2,756
With no related allowance - Unpaid principal balance	8,618	6,674
With related allowance - Recorded investment	1,965	1,745
With related allowance - Unpaid principal balance	2,107	1,752
Related allowance	622	374
Recorded investment	6,783	4,501
Unpaid principal balance	10,725	8,426
Owner Occupied Real Estate [Member]
With no related allowance - Recorded investment	2,093	2,595
With no related allowance - Unpaid principal balance	2,241	2,743
With related allowance - Recorded investment	1,307	1,203
With related allowance - Unpaid principal balance	1,314	1,206
Related allowance	201	235
Recorded investment	3,400	3,798
Unpaid principal balance	3,555	3,949
Consumer Portfolio Segment [Member]
With no related allowance - Recorded investment	638	655
With no related allowance - Unpaid principal balance	986	981
With related allowance - Recorded investment	152	347
With related allowance - Unpaid principal balance	153	379
Related allowance	68	217
Recorded investment	790	1,002
Unpaid principal balance	1,139	1,360
Residential Portfolio Segment [Member]
With no related allowance - Recorded investment
With no related allowance - Unpaid principal balance
With related allowance - Recorded investment
With related allowance - Unpaid principal balance
Related allowance
Recorded investment
Unpaid principal balance