Goodwill and Related Intangible Assets (Schedule of Changes in Carrying Amount of Goodwill) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Goodwill [Roll Forward]
Balance at December 31, 2018	$ 323,671
Adjustments to prior year acquisitions	(172)
Foreign currency translation	520
Balance at June 30, 2019	324,019
Residential Products
Goodwill [Roll Forward]
Balance at December 31, 2018	198,075
Adjustments to prior year acquisitions	0
Foreign currency translation	0
Balance at June 30, 2019	198,075
Industrial and Infrastructure Products
Goodwill [Roll Forward]
Balance at December 31, 2018	53,769
Adjustments to prior year acquisitions	0
Foreign currency translation	229
Balance at June 30, 2019	53,998
Renewable Energy & Conservation
Goodwill [Roll Forward]
Balance at December 31, 2018	71,827
Adjustments to prior year acquisitions	(172)
Foreign currency translation	291
Balance at June 30, 2019	$ 71,946

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://fasb.org/us-gaap/role/ref/legacyRef
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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