Goodwill and Related Intangible Assets (Schedule of Impairment Charges) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Impairment of indefinite-lived intangibles	$ 9,048	$ 4,863	$ 2,700
Impairment of definite-lived intangibles	198	0	705
Residential Products
Finite-Lived Intangible Assets [Line Items]
Impairment of indefinite-lived intangibles	0	440	1,200
Impairment of definite-lived intangibles	0	0	0
Industrial and Infrastructure Products
Finite-Lived Intangible Assets [Line Items]
Impairment of indefinite-lived intangibles	7,980	4,423	1,500
Impairment of definite-lived intangibles	0	0	705
Renewable Energy & Conservation
Finite-Lived Intangible Assets [Line Items]
Impairment of indefinite-lived intangibles	1,068	0	0
Impairment of definite-lived intangibles	$ 198	$ 0	$ 0