Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consolidated Statements of Comprehensive Income (Loss)
Net income	$ 8,099	$ 10,488	$ 109,982
Other comprehensive income (loss), net of tax -
Unrealized holding losses arising during period	(4)	(24)	(3)
Retirement plan gain (loss)	(31,124)	38,459	11,490
Net tax benefit (cost) on other comprehensive income	11,897	(14,701)	17,581
Other comprehensive income (loss), net of tax	(19,231)	23,734	29,068
Comprehensive income (loss)	$ (11,132)us-gaap_ComprehensiveIncomeNetOfTax	$ 34,222us-gaap_ComprehensiveIncomeNetOfTax	$ 139,050us-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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to parent entity.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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