Goodwill And Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Schedule of Goodwill and Intangible Assets [Line Items]
Amortization of intangible assets	$ 2,981	$ 2,974
Customer Relationships [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets	10 years 9 months 18 days
Trade Name [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets	11 years 3 months 18 days
Non-Compete Agreements [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets	10 years 2 months 12 days
Backlog [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets	9 months