Commitments, Contingencies and Uncertainties (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Operating Leased Assets [Line Items]
Operating leases, future minimum payments due	$ 411.5
Revenue Equipment [Member]
Operating Leased Assets [Line Items]
Operating leases, future minimum payments due	$ 108.9
Operating lease term	4 years