OTHER ACCRUED LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Other Liabilities Disclosure [Abstract]
Accrued and deferred compensation	$ 19,473	$ 22,543
Accrued benefits and workers' compensation claims	5,733	6,241
Unearned revenue and customer deposits	2,172	2,024
Due to contracts and agencies	3,305	3,325
Current portion of operating lease	1,757	1,452
Other	4,123	2,988
Total other accrued liabilities	$ 36,563	$ 38,573
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Amount of expenses incurred but not yet paid nor invoiced, and liabilities classified as other.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer, classified as current.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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-Name Accounting Standards Codification
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Indicates line item in statement of financial position that includes current operating lease liability.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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