Accumulated Other Comprehensive Loss (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Amounts reclassified out of each component of accumulated other comprehensive income (loss)
Net of tax	$ 3,699
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	6,141
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Tax	(2,442)
Amortization of pension and other postretirement benefit plans \| Amount Reclassified from Accumulated Other Comprehensive Loss
Amounts reclassified out of each component of accumulated other comprehensive income (loss)
Prior service credit	(1,383)
Net actuarial loss	$ 7,524

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

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

-Publisher FASB

-Name Accounting Standards Codification

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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.

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

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

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Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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

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