CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Total revenue	$ 1,569.4	$ 1,773.3	$ 1,556.8
Operating expenses:
Salaries, wages and employee benefits	412.4	402.4	378.3
Operations and maintenance	168.9	162.5	147.8
Administrative	78.5	72.4	64.7
Insurance and claims	61.4	76.7	61.3
Acquisition-related transaction expenses	1.5	3.8	0.0
Depreciation and amortization	106.5	92.8	88.1
Gain on disposition of property and equipment	(12.3)	(21.0)	(17.1)
Impairment	17.9	9.4	0.0
Restructuring	0.5	2.4	0.3
Total operating expenses	1,533.2	1,674.9	1,444.0
Income from operations	36.2	98.4	112.8
Other expense (income):
Interest income	(4.6)	(2.8)	(0.3)
Interest expense	52.2	35.4	33.5
Change in fair value of warrant liability	0.0	(4.7)	(1.6)
Other	(1.0)	0.7	(0.8)
Total other expense	46.6	28.6	30.8
Income (loss) before income taxes	(10.4)	69.8	82.0
Income tax expense	7.3	19.6	26.0
Net income (loss)	(17.7)	50.2	56.0
Other comprehensive income (loss):
Foreign currency translation adjustments	0.5	(0.4)	0.0
Comprehensive income (loss)	(17.2)	49.8	56.0
Net income	(17.7)	50.2	56.0
Net income (loss) attributable to common stockholders	$ (27.0)	$ 44.5	$ 51.0
Earnings (loss) per common share:
Basic	$ (0.59)	$ 0.73	$ 0.79
Diluted	$ (0.59)	$ 0.7	$ 0.77
Weighted-average common shares outstanding:
Basic	45,822,936	60,459,451	63,744,456
Diluted	45,822,936	63,283,502	65,409,258
Series A
Other comprehensive income (loss):
Less dividends to convertible preferred stockholders	$ (5.0)	$ (5.0)	$ (5.0)
Weighted-average common shares outstanding:
Dividends declared per convertible preferred share	$ 7.63	$ 7.63	$ 7.63
Series B perpetual preferred stock
Other comprehensive income (loss):
Less dividends to convertible preferred stockholders	$ (4.3)	$ (0.7)	$ 0.0
Weighted-average common shares outstanding:
Dividends declared per convertible preferred share	$ 74.94	$ 11.46	$ 0
Company freight
Revenues:
Total revenue	$ 654.9	$ 650.3	$ 629.7
Operating expenses:
Purchased freight	542.0	698.0	598.5
Owner operator freight
Revenues:
Total revenue	422.3	509.9	486.5
Brokerage
Revenues:
Total revenue	242.1	321.2	269.0
Logistics
Revenues:
Total revenue	59.9	53.8	39.2
Fuel surcharge
Revenues:
Total revenue	190.2	238.1	132.4
Operating expenses:
Fuel	139.8	159.6	107.3
Service
Operating expenses:
Taxes and licenses	$ 16.1	$ 15.9	$ 14.8