CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Comprehensive income (loss)
Net income (loss)	$ (12,277)	$ 23,986	$ (16,678)	$ 49,032
Other comprehensive income (loss) before income tax effect:
Net unrealized gain (loss) on financial instruments	26	(27)	(220)	(33)
Net loss (gain) reclassified to income on financial instruments	209	(39)	481	(50)
Net gain on foreign currency cash flow hedges reclassified to income	(46)	(47)	(93)	(93)
Defined benefit plans and other postretirement benefits:
Net gain (loss) arising during the period	49	(5,769)	49	(5,769)
Amortization of prior service benefit	(1,031)	(15,501)	(2,056)	(30,620)
Amortization of net loss	2,941	6,995	5,125	13,280
Other comprehensive income (loss) before income tax effect	2,148	(14,388)	3,286	(23,285)
Income tax effect	(383)	(2,513)	(765)	(4,973)
Other comprehensive income (loss)	1,765	(16,901)	2,521	(28,258)
Comprehensive income (loss)	$ (10,512)	$ 7,085	$ (14,157)	$ 20,774