Identified Intangible Assets and Goodwill, Net Schedule of Goodwill (Details) $ in Thousands	6 Months Ended
Jun. 30, 2018 USD ($)
Goodwill [Line Items]
Goodwill	$ 35,477
Goodwill, acquisitions	1,013
Goodwill, translation and other adjustments	(327)
Goodwill	36,163
Utility [Member]
Goodwill [Line Items]
Goodwill	3,424
Goodwill, acquisitions	0
Goodwill, translation and other adjustments	0
Goodwill	3,424
Residential commercial [Member]
Goodwill [Line Items]
Goodwill	32,053
Goodwill, acquisitions	1,013
Goodwill, translation and other adjustments	(327)
Goodwill	$ 32,739

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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