SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Prepaid Expenses and Other (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Chassis converter pool agreements	$ 22,273	$ 18,326
Income tax receivables	9,872	10,821
Insurance premiums & maintenance agreements	3,313	6,860
Assets held for sale	3,039	10,777
All other	12,764	10,515
Prepaid expenses and other	$ 51,261	$ 57,299

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Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Amount of current assets classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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The prepaid amount of chassis converter pool agreements.

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