Property, Plant and Equipment Capital Leases (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Capital Leased Assets [Line Items]
Capital Lease Obligations	$ 96,015	$ 93,745
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation	50,371	44,726
jewell ridge pipeline [Member]
Capital Leased Assets [Line Items]
Capital Lease Obligations	66,919
Vehicles [Member]
Capital Leased Assets [Line Items]
Capital Lease Obligations	10,652	9,248
Computer Equipment [Member]
Capital Leased Assets [Line Items]
Capital Lease Obligations	$ 18,444	$ 17,578

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant