Note 8 - Deferred Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Other benefit obligations	$ 9,396	$ 8,305
Equity-based compensation	1,868
Accounts receivable	327	$ 236
Other	839	688
Deferred Tax Assets, Net	12,430	9,229
Property, plant and equipment	122,789	134,729
Goodwill and other intangible assets	166,268	164,591
Deferred Tax Liabilities	289,057	299,320
Deferred Income Tax Liabilities, Net	$ 276,627	$ 290,091