Number of customers acquired through acquisition

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The amount, measured at acquisition-date fair value, of all liabilities assumed that arise from contingencies and were recognized by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Summary of Accounting Policies Acquisitions Additional information (Details)	12 Months Ended
	Dec. 31, 2017 USD ($)	Jun. 30, 2018 USD ($)
Business Acquisition [Line Items]
Number of customers acquired through acquisition	800
ARM Energy [Member]
Business Acquisition [Line Items]
Business Combination, Liabilities Arising from Contingencies, Amount Recognized		$ 2,500,000.0
Central Gas [Member]
Business Acquisition [Line Items]
Number of customers acquired through acquisition	325
Unregulated Energy [Member] \| ARM [Member]
Business Acquisition [Line Items]
Goodwill, Acquired During Period	$ 6,800,000