Supplementary Balance Sheet Detail (Schedule Of Amounts Recognized In Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Balance Sheet Related Disclosures [Abstract]
Raw materials and supplies	$ 80,408	$ 122,218
Work in process	136,858	176,141
Finished goods	78,196	84,544
Inventories	295,462	382,903
Prepaid expenses	9,297	9,923
Current portion of deferred taxes	0	28,426
Value added tax and other indirect taxes receivable	10,087	39,837
Other current assets	2,290	3,437
Prepaid Expense and Other Assets, Current	21,674	81,623
Land and improvements	54,064	36,375
Buildings	76,331	193,427
Machinery and equipment and other	486,194	1,212,120
Construction in progress	44,291	58,899
Property, plant and equipment	660,880	1,500,821
Payrolls (including incentive programs)	4,588	6,151
Customer prepayments	559	5,534
Employee compensation and benefits	7,842	8,932
Other	16,790	22,702
Accrued liabilities, net	29,779	43,319
Postretirement benefits	20,019	24,833
Pension and related benefits	55,364	65,882
Other	20,102	16,851
Other long - term obligations	$ 95,485	$ 107,566