Quarterly report pursuant to Section 13 or 15(d)

Significant Accounting Policies (Disaggregated Revenue) (Details)

v3.19.1
Significant Accounting Policies (Disaggregated Revenue) (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Disaggregation Of Revenue [Line Items]    
Revenue from operations $ 990,782 $ 925,020
LTL Service Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Revenue from operations 976,563 911,054
Other Service Revenue [Member]    
Disaggregation Of Revenue [Line Items]    
Revenue from operations $ 14,219 $ 13,966