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Description of Business and Summary of Significant Accounting Policies (Details 1) | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
consolidated gross trade accounts receivable [Member] |  |  |
Summary of concentration risk percentage of consolidated revenues from utility companies [Abstract] |  |  |
Description of concentration risk percentage | No other single utility company accounted for 10% or greater of our consolidated gross trade accounts receivable. |  |
Con Edison [Member] | consolidated revenues [Member] |  |  |
Summary of concentration risk percentage of consolidated revenues from utility companies [Abstract] |  |  |
Concentration risk percentage | 23.00% | 23.00% | 25.00%
Con Edison [Member] | consolidated gross trade accounts receivable [Member] |  |  |
Summary of concentration risk percentage of consolidated revenues from utility companies [Abstract] |  |  |
Concentration risk percentage | 22.00% | 25.00% |
National Grid Usa [Member] | consolidated revenues [Member] |  |  |
Summary of concentration risk percentage of consolidated revenues from utility companies [Abstract] |  |  |
Concentration risk percentage | 12.00% |  | 10.00%
Description of concentration risk percentage |  | Less than 10 |
West Penn Power [Member] | consolidated revenues [Member] |  |  |
Summary of concentration risk percentage of consolidated revenues from utility companies [Abstract] |  |  |
Concentration risk percentage |  | 10.00% | 11.00%
Description of concentration risk percentage | Less than 10 |  |
Penelec [Member] | consolidated revenues [Member] |  |  |
Summary of concentration risk percentage of consolidated revenues from utility companies [Abstract] |  |  |
Concentration risk percentage |  |  | 10.00%
Description of concentration risk percentage | Less than 10 | Less than 10 |

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611 + Details
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