Employee Benefits Plans (Details 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Amounts recognized in the Consolidated Balance Sheets
Noncurrent asset	$ 2,698	$ 23,556
Pension Plans [Member]
Amounts recognized in the Consolidated Balance Sheets
Noncurrent asset	2,698	23,556
Current liability	(3,739)	(3,660)
Noncurrent liability	(444,657)	(292,155)
Net amount recognized	(445,698)	(272,259)
Amounts recognized in accumulated other comprehensive loss (pre-tax)
Prior service credit	(195)	(2,153)
Net actuarial loss (gain)	905,976	745,356
Net amount recognized	$ 905,781	$ 743,203

The pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

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Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

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The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

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The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan.

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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

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This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

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