General - Contributions to Revenues and Profits Since Acquisitions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Business Acquisition [Line Items]
Goodwill impairment	$ 45,390	$ 0	$ 45,390	$ 0
Restructuring charges	5,439	212	5,439	8,544
Underground Solutions
Business Acquisition [Line Items]
Revenues	9,304	8,273	25,349	23,916
Net Loss	374	(101)	2,049	1,661
Fyfe Europe
Business Acquisition [Line Items]
Revenues	35	15	396	23
Net Loss	1,857	202	2,001	300
Goodwill impairment	1,800		1,800
LMJ
Business Acquisition [Line Items]
Revenues	342	1,446	2,702	2,779
Net Loss	596	134	2,213	221
Restructuring charges	100		100
Concrete Solutions
Business Acquisition [Line Items]
Revenues	1,561	1,344	4,276	1,344
Net Loss	2,080	(68)	2,033	(68)
Goodwill impairment	2,200		2,200
Environmental Techniques
Business Acquisition [Line Items]
Revenues	1,322		3,245
Net Loss	166		561
Corporate, Non-Segment | Underground Solutions
Business Acquisition [Line Items]
Net Loss	$ 700	$ 300	$ 1,800	$ 1,600