Note 9 - Fair Value Measurements and Disclosures (Details) - Financial Assets Measured at Fair Value on a Recurring and Nonrecurring Basis (USD $)	Jun. 30, 2013	Dec. 31, 2012
Securities available-for-sale
Securities available-for-sale	$ 380,364,000	$ 401,502,000
Recurring fair value measurements	380,364,000	401,502,000
Nonrecurring fair value measurements
Nonrecurring fair value measurements	7,554,000	6,280,000
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Securities available-for-sale	70,474,000	104,130,000
US Government Agencies Debt Securities [Member]
Securities available-for-sale
Securities available-for-sale	70,474,000	104,130,000
State and Municipal [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Securities available-for-sale	86,715,000	86,789,000
State and Municipal [Member]
Securities available-for-sale
Securities available-for-sale	86,715,000	86,789,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Securities available-for-sale	126,945,000	107,973,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale
Securities available-for-sale	126,945,000	107,973,000
Collateralized Mortgage Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Securities available-for-sale	85,678,000	94,091,000
Collateralized Mortgage Obligations [Member]
Securities available-for-sale
Securities available-for-sale	85,678,000	94,091,000
Pooled Trust Preferred Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale
Securities available-for-sale	2,091,000	1,962,000
Pooled Trust Preferred Securities [Member]
Securities available-for-sale
Securities available-for-sale	2,091,000	1,962,000
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Securities available-for-sale	3,991,000	2,502,000
Corporate Debt Securities [Member]
Securities available-for-sale
Securities available-for-sale	3,991,000	2,502,000
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale
Securities available-for-sale	4,470,000	4,055,000
Equity Securities [Member]
Securities available-for-sale
Securities available-for-sale	4,470,000	4,055,000
Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	5,612,000	5,832,000
Impaired Loans [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	5,612,000	5,832,000
Mortgage Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	504,000	448,000
Mortgage Servicing Rights [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	504,000	448,000
Loans Held For Sale [Member] | Fair Value, Inputs, Level 2 [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	1,328,000
Loans Held For Sale [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	1,328,000
OREO [Member] | Fair Value, Inputs, Level 1 [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	110,000
OREO [Member]
Nonrecurring fair value measurements
Nonrecurring fair value measurements	110,000
Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale
Securities available-for-sale	4,470,000	4,055,000
Recurring fair value measurements	4,470,000	4,055,000
Nonrecurring fair value measurements
Nonrecurring fair value measurements	110,000
Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale
Securities available-for-sale	373,803,000	395,485,000
Recurring fair value measurements	373,803,000	395,485,000
Nonrecurring fair value measurements
Nonrecurring fair value measurements	1,328,000
Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale
Securities available-for-sale	2,091,000	1,962,000
Recurring fair value measurements	2,091,000	1,962,000
Nonrecurring fair value measurements
Nonrecurring fair value measurements	$ 6,116,000	$ 6,280,000