Leases - Summary of Lease Cost (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Leases [Abstract]
Operating Lease, Cost	[1]	$ 27.2	$ 36.9
Short-term cost	[2]	4.9	9.6
Variable lease cost	[2]	4.7	2.5
Total lease cost		$ 36.8	$ 49.0

[1] Operating lease cost represents non-cash amortization of ROU assets and accretion of the discounted lease liabilities and is segregated on the statements of consolidated cash flows.

[2] These operating expenses are classified and recorded primarily within purchased transportation.