Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	$ 17,130		$ 16,605
Cash [Member] | Fair Value, Inputs, Level 1 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	737		1,319
Cash [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	737		1,319
Equity Securities US Companies [Member] | Fair Value, Inputs, Level 1 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	8,729		8,091
Equity Securities US Companies [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	8,729		8,091
Equity Securities International Companies [Member] | Fair Value, Inputs, Level 1 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	274		137
Equity Securities International Companies [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	274		137
Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	1,861	[1]	2,490	[1]
Equity Funds [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	1,861	[1]	2,490	[1]
US Government Corporations and Agencies Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	107		358
US Government Corporations and Agencies Securities [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	107		358
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	365		398
US States and Political Subdivisions Debt Securities [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	365		398
Corporate Debt Securities [Member] | External Credit Rating, Investment Grade [Member] | Fair Value, Inputs, Level 2 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	5,057	[2]	3,812	[2]
Corporate Debt Securities [Member] | External Credit Rating, Investment Grade [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	5,057	[2]	3,812	[2]
Fair Value, Inputs, Level 1 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	11,601		12,037
Fair Value, Inputs, Level 2 [Member]
Note 8 - Employee Benefit Plans (Details) - Fair Value Measurements [Line Items]
Pension plan’s assets	$ 5,529		$ 4,568

[1] This category comprises actively managed equity funds invested in large-cap and mid-cap U.S. companies.

[2] This category represents investment grade bonds of U.S. issuers from diverse industries.