CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
NET INCOME (LOSS)	$ 46,177us-gaap_NetIncomeLoss	$ 15,811us-gaap_NetIncomeLoss	$ (7,732)us-gaap_NetIncomeLoss
Pension and other postretirement benefit plans:
Net gain from curtailment, net of tax of: (2013 - $11,384)		17,878
Net actuarial gain (loss), net of tax of: (2014 - $8,639; 2013 - $11,892; 2012 - $3,709)	(13,567)	18,683	(5,830)
Pension settlement expense, net of tax of: (2014 - $2,565; 2013 - $821)	4,030	1,290
Amortization of unrecognized net periodic benefit costs, net of tax of: (2014 - $979; 2013 - $3,014; 2012 - $4,354)
Net actuarial loss	1,652	4,847	6,957
Prior service credit	(116)	(116)	(116)
Interest rate swap and foreign currency translation:
Change in unrealized loss on interest rate swap, net of tax of: (2014 - $226)	(350)
Change in foreign currency translation, net of tax of: (2014 - $137; 2013 - $79; 2012 - $10)	(216)	(122)	19
OTHER COMPREHENSIVE INCOME (LOSS), net of tax	(8,567)	42,460	1,030
COMPREHENSIVE INCOME (LOSS)	$ 37,610us-gaap_ComprehensiveIncomeNetOfTax	$ 58,271us-gaap_ComprehensiveIncomeNetOfTax	$ (6,702)us-gaap_ComprehensiveIncomeNetOfTax

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Net of tax amount of the gain (loss) adjustment to other comprehensive income (loss) resulting from the curtailment of the entity's defined benefit pension and other postretirement plans.

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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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss), attributable to parent entity.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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