XML 58 R45.htm IDEA: XBRL DOCUMENT v3.10.0.1
ACQUISITIONS (Details) - USD ($)
$ in Thousands
9 Months Ended
Jun. 15, 2018
Apr. 02, 2018
Sep. 30, 2018
Dec. 31, 2017
Business Acquisition [Line Items]        
Goodwill     $ 493,169 $ 395,504
MXD Group        
Business Acquisition [Line Items]        
Purchase price of outstanding equity in acquisition   $ 118,000    
Acquisition transaction costs     1,000  
Customer relationships and other intangibles   23,651    
Goodwill   $ 81,848    
Metro        
Business Acquisition [Line Items]        
Purchase price of outstanding equity in acquisition $ 52,000      
Acquisition transaction costs     $ 500  
Customer relationships and other intangibles 400      
Tangible assets net of liabilities assumed 20,000      
Goodwill $ 31,000      
Customer Relationships | MXD Group        
Business Acquisition [Line Items]        
Amortization period     8 years