Note 19 - Fair Value Measurements - Assets Measured at Fair Value on Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Securities available for sale	$ 261,841	$ 271,172
Equity securities (included in other assets)	1,715
Fair Value, Measurements, Recurring [Member]
Securities available for sale	261,841	271,172
Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale	91,257	112,649
Fair Value, Measurements, Recurring [Member] | Agency Collateralized Mortgage Obligations [Member]
Securities available for sale	32,992	15,323
Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member]
Securities available for sale	74,504	69,028
Fair Value, Measurements, Recurring [Member] | Municipal Notes [Member]
Securities available for sale	63,088	74,172
Fair Value, Measurements, Nonrecurring [Member]
Impaired loans	3,737	3,371
Loans held for sale	2,849	2,630
Foreclosed real estate	3,142	3,971
Fair Value, Measurements, Nonrecurring [Member] | Residential Mortgage Segment [Member]
Impaired loans	2,181	2,872
Foreclosed real estate	33	443
Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Segment [Member]
Impaired loans	422	401
Foreclosed real estate	3,109	3,528
Fair Value, Measurements, Nonrecurring [Member] | Land Segment [Member]
Impaired loans	152
Fair Value, Measurements, Nonrecurring [Member] | Commercial Business Segment [Member]
Impaired loans	426	38
Fair Value, Measurements, Nonrecurring [Member] | Residential Construction [Member]
Impaired loans	521
Fair Value, Measurements, Nonrecurring [Member] | Home Equity and Second Mortgage [Member]
Impaired loans	35	60
Fair Value, Inputs, Level 1 [Member]
Equity securities (included in other assets)	1,715
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Securities available for sale
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | Agency Collateralized Mortgage Obligations [Member]
Securities available for sale
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member]
Securities available for sale
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member] | Municipal Notes [Member]
Securities available for sale
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member]
Impaired loans
Loans held for sale
Foreclosed real estate
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Residential Mortgage Segment [Member]
Impaired loans
Foreclosed real estate
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Segment [Member]
Impaired loans
Foreclosed real estate
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Land Segment [Member]
Impaired loans
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Commercial Business Segment [Member]
Impaired loans
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Residential Construction [Member]
Impaired loans
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Home Equity and Second Mortgage [Member]
Impaired loans
Fair Value, Inputs, Level 2 [Member]
Equity securities (included in other assets)
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Securities available for sale	261,841	271,172
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale	91,257	112,649
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Agency Collateralized Mortgage Obligations [Member]
Securities available for sale	32,992	15,323
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member]
Securities available for sale	74,504	69,028
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Municipal Notes [Member]
Securities available for sale	63,088	74,172
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member]
Impaired loans
Loans held for sale	2,849	2,630
Foreclosed real estate
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Residential Mortgage Segment [Member]
Impaired loans
Foreclosed real estate
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Segment [Member]
Impaired loans
Foreclosed real estate
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Land Segment [Member]
Impaired loans
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Commercial Business Segment [Member]
Impaired loans
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Residential Construction [Member]
Impaired loans
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Home Equity and Second Mortgage [Member]
Impaired loans
Fair Value, Inputs, Level 3 [Member]
Equity securities (included in other assets)
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Securities available for sale
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Agency Collateralized Mortgage Obligations [Member]
Securities available for sale
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | US Government Agencies Debt Securities [Member]
Securities available for sale
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member] | Municipal Notes [Member]
Securities available for sale
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member]
Impaired loans	3,737	3,371
Loans held for sale
Foreclosed real estate	3,142	3,971
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Residential Mortgage Segment [Member]
Impaired loans	2,181	2,872
Foreclosed real estate	33	443
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Commercial Real Estate Segment [Member]
Impaired loans	422	401
Foreclosed real estate	3,109	3,528
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Land Segment [Member]
Impaired loans	152
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Commercial Business Segment [Member]
Impaired loans	426	38
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Residential Construction [Member]
Impaired loans	521
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Home Equity and Second Mortgage [Member]
Impaired loans	$ 35	$ 60