Goodwill and Related Intangible Assets (Schedule of Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Balance at	$ 292,390
Foreign currency translation	2,468
Balance at	294,858
Accumulated impairment losses	234,490	$ 234,490
Residential Products
Goodwill [Roll Forward]
Balance at	181,285
Foreign currency translation	0
Balance at	181,285
Industrial and Infrastructure Products
Goodwill [Roll Forward]
Balance at	53,704
Foreign currency translation	298
Balance at	54,002
Renewable Energy & Conservation
Goodwill [Roll Forward]
Balance at	57,401
Foreign currency translation	2,170
Balance at	$ 59,571