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Energy and Related Sales, Net (Tables) | 12 Months Ended
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Dec. 31, 2012
Energy and Related Sales, Net [Abstract] |
Summary of energy and related sales net |
In thousands |  |  | 2012 |  |  |  | 2011 |  |  |  | 2010 |
Energy sales |  | $ | 5,284 |  |  | $ | 10,992 |  |  | $ | 14,296 |
Costs to produce |  |  | (4,187 | ) |  |  | (9,319 | ) |  |  | (10,403 | )
Net energy sales |  |  | 1,097 |  |  |  | 1,673 |  |  |  | 3,893 |
Renewable energy credits |  |  | 5,903 |  |  |  | 7,671 |  |  |  | 6,760 |
Total energy and related sales, net |  | $ | 7,000 |  |  | $ | 9,344 |  |  | $ | 10,653 |

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