XML 57 R44.htm IDEA: XBRL DOCUMENT v3.8.0.1
Business Combinations - 2016 Combinations (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
May 30, 2017
Nov. 18, 2016
Jun. 24, 2016
Jan. 29, 2016
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Jun. 30, 2016
Business combinations                    
Fair value of consideration $ 2,300                  
Operating income         $ 27,862 $ 11,419 $ 81,567 $ 28,825    
Goodwill         151,118   151,118   $ 127,226  
Pipe Jacking Unlimited Inc | Vadnais                    
Business combinations                    
Purchase of property, plant and equipment     $ 13,400              
Mueller | Aevenia                    
Business combinations                    
Fair value of consideration       $ 4,100            
Fixed assets                   $ 2,000
Goodwill                   2,000
Fair value of inventory acquired                   $ 100
The period of time goodwill is deductible for income tax purposes       15 years            
Northern | Aevenia                    
Business combinations                    
Fair value of consideration   $ 6,800                
Decrease to goodwill         (100)          
Fixed assets         100   100      
Goodwill         3,700   3,700      
The period of time goodwill is deductible for income tax purposes   15 years                
Northern | Customer relationships | Aevenia                    
Business combinations                    
Intangibles assets         $ 3,000   $ 3,000