Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	$ 618,297	$ 626,388
US Government-sponsored Enterprises Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	131,157	109,448
US States and Political Subdivisions Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	138,475	135,766
Residential Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	328,257	370,489
Commercial Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	13,170	2,512
Corporate Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	6,386	6,307
Mutual Funds and Equity Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	852	1,866
Fair Value, Inputs, Level 1 [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	852	1,866
Fair Value, Inputs, Level 1 [Member] | US Government-sponsored Enterprises Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 1 [Member] | US States and Political Subdivisions Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 1 [Member] | Residential Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 1 [Member] | Commercial Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 1 [Member] | Mutual Funds and Equity Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	852	1,866
Fair Value, Inputs, Level 2 [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	617,445	624,522
Fair Value, Inputs, Level 2 [Member] | US Government-sponsored Enterprises Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	131,157	109,448
Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	138,475	135,766
Fair Value, Inputs, Level 2 [Member] | Residential Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	328,257	370,489
Fair Value, Inputs, Level 2 [Member] | Commercial Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	13,170	2,512
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	6,386	6,307
Fair Value, Inputs, Level 2 [Member] | Mutual Funds and Equity Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 3 [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 3 [Member] | US Government-sponsored Enterprises Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 3 [Member] | US States and Political Subdivisions Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 3 [Member] | Residential Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 3 [Member] | Commercial Mortgage Backed Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	0	0
Fair Value, Inputs, Level 3 [Member] | Mutual Funds and Equity Securities [Member]
Note 12 - Fair Value Measurements (Details) - Available for Sale Investment Securities Measured at Fair Value on a Recurring Basis [Line Items]
Available for Sale Investment Securities	$ 0	$ 0