Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Other Liabilities, Noncurrent [Abstract]
Contract liabilities, net of current portion	$ 34,866	$ 30,925
Asset retirement obligations	7,647	1,961
Deferred payments related to acquisitions	715	4,963
Employee separation costs	0	1,838
Other	2,827	1,764
Other long-term liabilities	$ 46,055	$ 41,451

Represents non-current deferred payments related to acquisitions.

No definition available.

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- Definition

Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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- Definition

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

+ References

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- Definition

Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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No definition available.

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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Carrying amount as of the balance sheet date of known and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid after one year or beyond the next operating cycle, if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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