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Leases (Details Textual) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Leases (Textual) [Abstract] |  |  |
Capital lease obligations outstanding | $ 12.5 |  |
Weighted average interest rate on capital leases | 7.68% |  |
Capital leases outstanding under Bossier City Financing Arrangement | 6.6 |  |
Amount placed in escrow under Financing Arrangement | 10 |  |
Financing arrangement proceeds held in escrow | 0.9 |  |
Rental expenses | $ 3.2 | $ 3.3 | $ 3.2

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- Definition Amount placed in escrow under Financing Arrangement proceeds. + References No definition available. + Details
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- Definition Capital lease obligation under financial arrangement. + References No definition available. + Details
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- Details
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- Definition 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. + References 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 + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717 + Details
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