Restructuring and Related Charges - Restructuring liability (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Schedule of restructuring liability
Beginning balance	$ 3,122	$ 8,283
Restructuring and other charges	1,190	0
Payments	(2,856)	(2,708)
Adjustments	0	0
Ending balance	1,456	5,575
Accounts payable and accrued expenses
Schedule of restructuring liability
Restructuring liabilities	1,500		$ 3,100
Severance And Other Employee Separation Costs \| CEC Integration Plan
Schedule of restructuring liability
Beginning balance	1,835	8,283
Restructuring and other charges	0	0
Payments	(733)	(2,708)
Adjustments	0	0
Ending balance	1,102	5,575
Severance And Other Employee Separation Costs \| 2020 Restructuring Plan
Schedule of restructuring liability
Beginning balance	1,287	0
Restructuring and other charges	1,190	0
Payments	(2,123)	0
Adjustments	0	0
Ending balance	$ 354	$ 0

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal 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, 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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