Condensed Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net loss	$ (97,218)	$ (128,363)	$ (318,217)	$ (270,618)
Derivative instruments
Comprehensive income (loss) before tax	520	1,346	1,298	(224)
Income tax benefit (provision)	(187)	(486)	(467)	82
Derivatives Qualifying as Hedges, Adjustment, Net of Tax	333	860	831	(142)
Pension, postretirement and other post-employment benefits
Comprehensive income (loss) before tax	(1,210)	1,277	(5,326)	4,981
Income tax benefit (provision)	435	(458)	1,917	(1,791)
Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	(775)	819	(3,409)	3,190
Available-for-sale securities
Comprehensive income (loss) before tax	(2,401)	1,136	(5,637)	7,648
Income tax benefit (provision)	864	(448)	2,029	(2,795)
Available-for-sale Securities Adjustment, Net of Tax	(1,537)	688	(3,608)	4,853
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(1,979)	2,367	(6,186)	7,901
Total comprehensive loss	$ (99,197)	$ (125,996)	$ (324,403)	$ (262,717)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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