Quarterly report pursuant to Section 13 or 15(d)

Backlog (Details Textual)

v3.10.0.1
Backlog (Details Textual) - USD ($)
$ in Millions
Sep. 30, 2018
Dec. 31, 2017
Construction [Member]    
Estimated Revenue From Uncompleted Contract $ 435.8 $ 426.7
Service [Member]    
Estimated Revenue From Uncompleted Contract $ 51.7 $ 34.7