Asset Acquisition (Clearfield PPA) (Details) (Clearfield Energy [Member], USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Clearfield Energy [Member]
Assets acquired:
Current assets	$ 17,622
Assets held for sale	19,500
Property, Plant, and Equipment	89,752
Goodwill	152,627
Intangibles	37,600
Liabilities assumed:
Current liabilities	(24,784)
Liabilities held for disposition	(2,627)
Deferred Taxes	(65,228)
Long term liabilities	(9,505)
Total Purchase Price	$ 214,957

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The amount of acquisition cost of a business combination allocated to current assets.

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The amount of acquisition cost of a business combination allocated to assets expected to be sold.

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The amount of acquisition cost of a business combination allocated to current liabilities of the acquired entity.

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

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Gross amount of acquisition cost of a business combination allocated to noncurrent deferred tax liabilities.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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

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Amount of acquisition cost of a business combination allocated to assets, excluding financial assets and goodwill, lacking physical substance.

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Amount of acquisition cost of a business combination allocated to other noncurrent liabilities not separately disclosed.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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Liability related to a disposal group that is held for sale and anticipated to be sold in less than one year. The liability is expected to be discharged as part of the plan of sale for the asset.

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No definition available.

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