Impairment of Long-Lived Assets and Goodwill (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Impairment expense	$ 25,523,000us-gaap_AssetImpairmentCharges	$ 0us-gaap_AssetImpairmentCharges
Southwest Segment \| Appleby
Impairment expense	22,800,000
Impairment related to intangibles	16,800,000
Impairment related to property, plant and equipment	6,000,000
Western Oklahoma Reporting Unit \| Southwest Segment
Goodwill impairment charge	2,700,000
Other reporting units
Goodwill impairment charge	$ 0

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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-Glossary Impairment

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