CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 8,422	$ 6,882
Pension and post-retirement obligations:
Amortization of actuarial (gains) losses and prior service credit to earnings, net of tax	(136)	474
Derivative instruments designated as cash flow hedges:
Change in fair value of derivatives, net of tax		(32)
Reclassification of realized loss to earnings, net of tax	408	2,290
Comprehensive income	8,694	9,614
Less: comprehensive income attributable to noncontrolling interest	98	99
Total comprehensive income attributable to common shareholders	$ 8,596	$ 9,515

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

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Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount after tax 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).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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