Details of Selected Balance Sheet Accounts - Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Details of Selected Balance Sheet Accounts [Abstract]
Accrued compensation	$ 13,391	$ 24,930
Insurance liabilities	7,641	9,108
Accrued taxes, other than income taxes	7,103	3,424
Accrued commissions	1,893	1,481
Other	10,795	9,897
Accrued liabilities	$ 40,823	$ 48,840

Details of Selected Balance Sheet Accounts [Abstract]

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. 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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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable to insurance entities to mitigate potential loss from various risks or to satisfy a promise to provide certain coverage's to employees. 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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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. 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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Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions. 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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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).

+ References

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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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