Leases - Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
Total lease cost	$ 22,179	$ 64,722
Vehicle Rents and General and Other Operating [Member]
Lessee, Lease, Description [Line Items]
Operating lease cost	19,917	59,156
Depreciation and Amortization [Member]
Lessee, Lease, Description [Line Items]
Amortization of finance lease assets	760	2,365
Interest Expense [Member]
Lessee, Lease, Description [Line Items]
Interest on lease liabilities	252	848
General and Other Operating [Member]
Lessee, Lease, Description [Line Items]
Short-term lease cost	$ 1,250	$ 2,353