Note 10 - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Inventory	$ 3,032	$ 3,313
Foreign tax credit carryforwards	3,990	19,925
Environmental	2,795	2,993
Net operating loss carryforwards (foreign)	1,191	3,381
Employee benefits	$ 14,978	18,879
Research & experimentation tax credit carryforwards		480
Alternative minimum tax credit carryforwards	$ 1,306	2,773
Property, plant and equipment	4,188	3,898
Other	6,251	5,605
Total gross deferred tax assets	37,731	61,247
Valuation allowance	(3,141)	(5,053)
Total deferred tax assets	34,590	56,194
Deferred tax liabilities:
Property, plant and equipment	(11,472)	(9,649)
Intangibles and other	(8,192)	(10,487)
Unremitted foreign earnings	(208)	(726)
Foreign tax allocation reserve	(2,071)	(1,856)
Other	(1,123)	(1,978)
Total deferred tax liabilities	(23,066)	(24,696)
Net deferred tax assets	11,524	31,498
Classified as follows in the consolidated balance sheet:
Non-current deferred tax asset	19,259	41,747
Non-current deferred tax liability	$ (7,735)	$ (10,249)