Quarterly report pursuant to Section 13 or 15(d)

Significant Accounting Policies Significant Accounting Policies (Disaggregated Revenue) (Details)

v3.10.0.1
Significant Accounting Policies Significant Accounting Policies (Disaggregated Revenue) (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Disaggregation of Revenue [Line Items]        
Revenue from operations $ 1,058,233 $ 872,987 $ 3,016,751 $ 2,466,995
LTL Service Revenue [Member]        
Disaggregation of Revenue [Line Items]        
Revenue from operations 1,041,854 859,832 2,971,399 2,426,419
Other Service Revenue [Member]        
Disaggregation of Revenue [Line Items]        
Revenue from operations $ 16,379 $ 13,155 $ 45,352 $ 40,576