Operations and Summary of Significant Accounting Policies - Goodwill Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Goodwill [Roll Forward]
Balance, beginning of period		$ 522,712	$ 278,706
Acquisition		0	1,272,403
Impairment	$ (14,751)	0	(1,028,397)	$ 0
Balance, ending of period		522,712	522,712	278,706
Expedited Freight
Goodwill [Roll Forward]
Balance, beginning of period		141,720	141,720
Acquisition		0	0
Impairment		0	0
Balance, ending of period		141,720	141,720	141,720
Omni Logistics
Goodwill [Roll Forward]
Balance, beginning of period		244,006	0
Acquisition		0	1,272,403
Impairment		0	(1,028,397)
Balance, ending of period		244,006	244,006	0
Intermodal
Goodwill [Roll Forward]
Balance, beginning of period		136,986	136,986
Acquisition		0	0
Impairment		0	0
Balance, ending of period		$ 136,986	$ 136,986	$ 136,986

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

- Definition

Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References + Details