XML 63 R52.htm IDEA: XBRL DOCUMENT v3.7.0.1
COMMITMENTS AND CONTINGENCIES (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Letter of credit    
Operating Leased Assets [Line Items]    
Outstanding letters of credit $ 7.0  
Building and terminal    
Operating Leased Assets [Line Items]    
Rent expense 0.8 $ 0.6
Tractor, trailer and other revenue equipment    
Operating Leased Assets [Line Items]    
Rent expense $ 3.9 $ 2.6