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GENERAL INFORMATION - GENERAL (Details) customer in Millions | Jun. 30, 2018 customer
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Electric |
Product information [Line Items] |
Number Of Customers | 1.6
Natural gas |
Product information [Line Items] |
Number Of Customers | 2.9
ATC |
Product information [Line Items] |
Equity method investment, ownership interest (as a percent) | 60.00%

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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