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Restructuring - Narrative (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
Restructuring - Narrative (Details) - USD ($) $ in Millions	Aug. 31, 2019	Jul. 31, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Activity
Restructuring, initiation date		Jul. 29, 2019
Restructuring, completion date	Aug. 31, 2019
FTFM pre-tax losses					$ 34.4
Truckload \| Other costs
Restructuring Activity
Restructuring reserve				$ 4.4	$ 5.1
Cash payments			$ 4.4	$ 1.5