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Operations and Significant Accounting Policies - Concentraion of Credit Risk (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Customer Information [Line Items] |  |  |
Major Customer, Percent of Total Revenue | 12.30% | 12.80% | 12.50%
NewPage Bankruptcy Pre-Petition Receivable | $ 3.2 |  |
Large Power Customer [Member] |  |  |
Customer Information [Line Items] |  |  |
Number of Customers | 9 |  |
Large Power Customers, Accounts Receivable | $ 11.6 | 9.3 |

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- Definition For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.9) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of bankruptcy claim settled. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 90-7 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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