Note 9 - Fair Value Measurements and Disclosures (Details) - Financial Assets Measured at Fair Value on a Recurring and Nonrecurring Basis (USD $)	Sep. 30, 2014	Dec. 31, 2013
Trading Securities
State and municipal securities	$ 4,122,000	$ 0
Securities available-for-sale
Available-for-sale securities	362,468,000	388,670,000
Recurring fair value measurements	366,590,000	388,670,000
Nonrecurring fair value measurements
Nonrecurring fair value measurements	1,581,000	3,626,000
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Trading Securities
State and municipal securities	4,122,000
Securities available-for-sale
Available-for-sale securities	74,133,000	87,199,000
US States and Political Subdivisions Debt Securities [Member]
Trading Securities
State and municipal securities	4,122,000
Securities available-for-sale
Available-for-sale securities	74,133,000	87,199,000
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Available-for-sale securities	56,322,000	71,639,000
US Government Agencies Debt Securities [Member]
Securities available-for-sale
Available-for-sale securities	56,322,000	71,639,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Available-for-sale securities	139,171,000	139,723,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale
Available-for-sale securities	139,171,000	139,723,000
Collateralized Mortgage Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Available-for-sale securities	77,027,000	75,394,000
Collateralized Mortgage Obligations [Member]
Securities available-for-sale
Available-for-sale securities	77,027,000	75,394,000
Pooled Trust Preferred Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale
Available-for-sale securities	2,462,000	2,069,000
Pooled Trust Preferred Securities [Member]
Securities available-for-sale
Available-for-sale securities	2,462,000	2,069,000
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Available-for-sale securities	6,060,000	6,021,000
Corporate Debt Securities [Member]
Securities available-for-sale
Available-for-sale securities	6,060,000	6,021,000
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale
Available-for-sale securities	7,293,000	6,625,000
Equity Securities [Member]
Securities available-for-sale
Available-for-sale securities	7,293,000	6,625,000
Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale
Available-for-sale securities	7,293,000	6,625,000
Recurring fair value measurements	7,293,000	6,625,000
Fair Value, Inputs, Level 2 [Member]
Trading Securities
State and municipal securities	4,122,000
Securities available-for-sale
Available-for-sale securities	352,713,000	379,976,000
Recurring fair value measurements	356,835,000	379,976,000
Fair Value, Inputs, Level 3 [Member] | Impaired Loans [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	1,475,000	3,107,000
Fair Value, Inputs, Level 3 [Member] | Mortgage Servicing Rights [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	106,000	519,000
Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale
Available-for-sale securities	2,462,000	2,069,000
Recurring fair value measurements	2,462,000	2,069,000
Nonrecurring fair value measurements
Nonrecurring fair value measurements	1,581,000	3,626,000
Impaired Loans [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	1,475,000	3,107,000
Mortgage Servicing Rights [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	$ 106,000	$ 519,000