Note 10 - Retirement and Postretirement Plans (Details) - Summary of Accumulated Other Comprehensive Income (Loss) Related to Pension and Other Benefits (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension Plan [Member]
Note 10 - Retirement and Postretirement Plans (Details) - Summary of Accumulated Other Comprehensive Income (Loss) Related to Pension and Other Benefits [Line Items]
Balance	$ (55,382)	$ 8,721	$ (1,668)	$ (850)
Actuarial gain (loss)	(64,103)	10,389	(818)
Other Pension Plan, Postretirement or Supplemental Plans [Member]
Note 10 - Retirement and Postretirement Plans (Details) - Summary of Accumulated Other Comprehensive Income (Loss) Related to Pension and Other Benefits [Line Items]
Balance	(1,903)	174
Actuarial gain (loss)	$ (2,077)	$ 174