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Description of Business and Summary of Significant Accounting Policies (Details 1)	12 Months Ended
	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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Description of concentration risk percentage.

+ References

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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

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