INCOME TAXES - Deferred income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of the deferred tax provision or benefit
Amortization, depreciation, and basis differences for property, plant and equipment and other long-lived assets	$ 1,744	$ 4,274	$ 1,409
Amortization of intangibles	6,127	(2,995)	(555)
Changes in reserves for workers' compensation, third-party casualty, and cargo claims	(4,975)	(3,713)	(3,296)
Revenue recognition	(50)	6	(1,434)
Allowance for credit losses	1,094	(388)	170
Nonunion pension and other retirement plans	(3)	(4)	(3)
Multiemployer pension fund withdrawal	180	172	164
Federal and state net operating loss carryforwards utilized (generated)	(758)	899	(300)
State depreciation adjustments	(456)	(915)	598
Share-based compensation	531	737	(949)
Valuation allowance increase (decrease)	44	(489)	912
Other accrued expenses	(2,143)	(3,069)	(4,056)
Prepaid expenses	313	(18)	(788)
Operating lease right-of-use assets/liabilities - net	(8,065)	(651)	(228)
Other	851	(250)	730
Deferred tax benefit	$ (5,566)	$ (6,404)	$ (7,626)

-- None. No documentation exists for this element. --

No definition available.

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- Definition

Represents the amount of deferred tax provision or (benefit) on allowance for doubtful accounts during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of deferred tax provision or (benefit) on amortization of intangible assets and impairment arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

This element represents the amount of deferred tax provision or (benefit) on equity-based compensation costs during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

Represents the deferred income tax expense benefit multiemployer pension fund withdrawal.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of deferred tax provision or (benefit) on operating lease right-of-use assets/liabilities - net during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of deferred tax provision or (benefit) on federal and state operating loss carryforwards during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

This element represents the amount of deferred tax provision or (benefit) on other costs not otherwise specified in the taxonomy during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of deferred tax provision or (benefit) on other accrued expenses during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

This element represents the amount of deferred tax provision or (benefit) on pension and other retirement plans costs during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of deferred tax provision or (benefit) on prepaid expenses during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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- Definition

This element represents the amount of deferred tax provision or (benefit) on amortization, depreciation and basis difference for property, plant and equipment and other long-lived assets (excluding intangible assets) arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

This element represents the amount of deferred tax provision or (benefit) on changes in reserves for workers' compensation and cargo claims arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

This element represents the amount of deferred tax provision or (benefit) on revenue recognition arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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- Definition

Represents the amount of deferred tax provision or (benefit) on state depreciation adjustments during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

+ Details

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- Definition

This element represents the amount of deferred tax provision or (benefit) on valuation allowance during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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- Definition

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

+ References

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