Restructuring and Related Charges - Restructuring liability (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Schedule of restructuring liability
Beginning balance	$ 3,122	$ 8,283
Restructuring and other charges	3,358	0
Payments	(4,581)	(3,986)
Adjustments	0	0
Ending balance	1,899	4,297
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	(1,344)	(3,986)
Adjustments	0	0
Ending balance	491	4,297
Severance And Other Employee Separation Costs \| 2020 Restructuring Plan
Schedule of restructuring liability
Beginning balance	1,287	0
Restructuring and other charges	3,358	0
Payments	(3,237)	0
Adjustments	0	0
Ending balance	$ 1,408	$ 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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-Publisher FASB
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-Section 45
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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