Consolidated Statements of Comprehensive (Loss) Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net loss	$ (136,319)us-gaap_NetIncomeLoss	$ (93,450)us-gaap_NetIncomeLoss	$ (153,294)us-gaap_NetIncomeLoss
Other comprehensive (loss) income, net of taxes:
Interest rate swaps (net of $0.7 million and $0.4 million tax benefit)	(1,037)	(601)	0
Qualified pension and post-retirement healthcare plans (net of $8.6 million tax benefit, $45.6 million tax expense, $19.7 million tax benefit, respectively)	(157,807)	96,811	(62,495)
Total other comprehensive income (loss)	(158,844)	96,210	(62,495)
Comprehensive income (loss)	$ (295,163)us-gaap_ComprehensiveIncomeNetOfTax	$ 2,760us-gaap_ComprehensiveIncomeNetOfTax	$ (215,789)us-gaap_ComprehensiveIncomeNetOfTax

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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