Restructuring Expenses - Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
2020 Restructuring charges:
Workforce reduction					$ 8,090
Other					107
Total 2020 restructuring charges	$ 0	$ 8,200	$ 0	$ 7,400	$ 8,197	$ 7,420

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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