Leases - Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Lessee, Lease, Description [Line Items]
Lease, Cost, Total	$ 25,126	$ 23,837	$ 75,194	$ 72,372
Vehicle Rents and General and Other Operating [Member]
Lessee, Lease, Description [Line Items]
Operating lease cost	23,255	20,902	69,518	64,445
Short-term lease cost	1,399	2,358	3,962	6,156
Depreciation and Amortization [Member]
Lessee, Lease, Description [Line Items]
Amortization of finance lease assets	355	439	1,326	1,319
Interest Expense [Member]
Lessee, Lease, Description [Line Items]
Interest on lease liabilities	$ 117	$ 138	$ 388	$ 452