INCOME TAXES (Deferred income taxes) (Details) - USD ($) $ in Thousands	2 Months Ended	10 Months Ended	12 Months Ended
Feb. 28, 2017	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components of the deferred tax provision or benefit
Amortization, depreciation, and basis differences for property, plant and equipment and other long-lived assets			$ 21,876	$ 12,182	$ 21,098
Amortization of intangibles			(1,030)	(3,623)	(3,184)
Changes in reserves for workers’ compensation, third-party casualty, and cargo claims			(812)	362	(674)
Revenue recognition			332	1,862	7
Allowance for doubtful accounts			(719)	(295)	307
Foreign tax credit carryforward utilized					434
Nonunion pension and other retirement plans			(1,977)	3,861	(234)
Deferred compensation plans			226	203	541
Federal net operating loss carryforwards utilized			28	161	70
State net operating loss carryforwards utilized (generated)			229	(304)	623
State depreciation adjustments			(1,244)	(758)	(657)
Share-based compensation			352	(681)	(621)
Valuation allowance increase (decrease)			401	(61)	22
Leases			16	(1)	(969)
Other accrued expenses			(852)	(4,108)	1,256
Provisional impact of the Tax Reform Act			(24,542)
Other			(2,497)	722	(1,584)
Deferred tax provision (benefit)			$ (10,213)	$ 9,522	$ 16,435
Statutory federal rate (as a percent)	35.00%	32.74%	35.00%	35.00%	35.00%
Federal statutory tax rate used to calculate provisional effect of the Tax Reform Act in the period of enactment (as a percent)			21.00%

-- 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.

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No definition available.

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Represents the amount of deferred tax provision or (benefit) on amortization of 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.

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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.

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

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No definition available.

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

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Represents the amount of deferred tax provision or (benefit) on domestic 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.

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This element represents the amount of deferred tax provision or (benefit) on state and local 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.

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No definition available.

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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.

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No definition available.

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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.

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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.

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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.

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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.

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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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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.

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This element represents the amount of deferred tax provision or (benefit) on foreign tax credit carryforwards, due to an increase or decrease in the entity's deferred tax assets and liabilities

+ References

No definition available.

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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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Amount of reasonable estimate for income tax benefit for remeasurement of deferred tax liability from change in tax rate pursuant to Tax Cuts and Jobs Act of 2017 for which accounting for tax effect is incomplete.

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No definition available.

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- Definition

Percentage of domestic federal statutory tax rate used to calculate effect of the Tax Cuts and Jobs Act of 2017 in the period of enactment.

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No definition available.

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- Definition

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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