Goodwill and Other Intangibles - Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Changes in the carrying amount of goodwill
Gross Goodwill	$ 1,839,123	$ 1,807,079
Additions	32,044
Accumulated Impairment Losses	(762,021)
Net Goodwill	1,077,102	1,045,058
Installation
Changes in the carrying amount of goodwill
Gross Goodwill	1,422,836	1,390,792
Additions	32,044
Accumulated Impairment Losses	(762,021)
Net Goodwill	660,815
Distribution
Changes in the carrying amount of goodwill
Gross Goodwill	416,287	$ 416,287
Net Goodwill	$ 416,287

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=64834752&loc=SL49117168-202975

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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.

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