Consolidated Statements Of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax	$ (729)	$ (890)	$ (2,396)
Derivative financial instruments adjustment, tax (benefit)	727	(550)	(112)
Net gains or losses and prior service costs, tax (benefit)	(1,874)	(226)	(22,445)
Amortization of prior service costs and net gains or losses, tax	$ 4,398	$ 5,823	$ 3,582