Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Condensed Consolidated Statements of Comprehensive Income [Abstract]
Net income (loss)	$ (435,424)	$ 6,630	$ (434,015)	$ 62,504
Other Comprehensive Income (Loss), net of income taxes [Abstract]
Pension, postretirement and other post-employment benefits, reclassifications into net income	(3,584)	293	(3,121)	866
Unrealized gains (losses) on available-for-sale securities	62	(1,434)	314	(687)
Unrealized gains and losses on derivatives, net of reclassifications into net income:
Unrealized gains (losses) on derivatives	991	(3,127)	2,751	6,374
Reclassifications of (gains) losses into net income	(518)	(4,360)	4,307	(6,484)
Total other comprehensive income (loss)	(3,049)	(8,628)	4,251	69
Total comprehensive income (loss)	$ (438,473)	$ (1,998)	$ (429,764)	$ 62,573