Restructuring Costs - Schedule of Restructuring Reserve Liabilities by Type (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2021
Restructuring Reserve [Roll Forward]
Beginning balance	$ 2,359	$ 3,959
Additions	0	0
Adjustments to accruals	(71)	(285)
Cash payments	(918)	(2,304)
Ending balance	1,370	1,370
Accrued Compensation and Related Costs
Restructuring Reserve [Roll Forward]
Beginning balance	1,851	3,369
Additions	0	0
Adjustments to accruals	(88)	(318)
Cash payments	(733)	(2,021)
Ending balance	1,030	1,030
Other Accrued Liabilities
Restructuring Reserve [Roll Forward]
Beginning balance	508	590
Additions	0	0
Adjustments to accruals	17	33
Cash payments	(185)	(283)
Ending balance	$ 340	$ 340

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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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to 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.

+ References

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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.

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