Restructuring and Related Impairment Charges - Restructuring Reserve (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2021
Employee Related Costs \| Restructuring Plan, 2020, 2018 and 2017
Restructuring Reserve [Roll Forward]
Balance at January 1, 2021		$ 12,868
Net additions (recoveries) charged to expense		(845)
Cash payments charged against reserve		(5,471)
Foreign exchange and other		(1,086)
Balance at September 30, 2021	$ 5,466	5,466
Contract Exit Costs \| Restructuring Plan, 2020, 2018 and 2017
Restructuring Reserve [Roll Forward]
Balance at January 1, 2021		61,642
Net additions (recoveries) charged to expense		17,814
Cash payments charged against reserve		(45,378)
Foreign exchange and other		(1,443)
Balance at September 30, 2021	32,635	32,635
Other Restructuring Related Costs \| Restructuring Plan, 2020, 2018 and 2017
Restructuring Reserve [Roll Forward]
Balance at January 1, 2021		6,098
Net additions (recoveries) charged to expense		(872)
Cash payments charged against reserve		(6,078)
Foreign exchange and other		140
Balance at September 30, 2021	(712)	(712)
Abandoned Facilities and Write Off of Fixed Assets \| 2020 Restructuring Plan
Restructuring Reserve [Roll Forward]
Net additions (recoveries) charged to expense	$ 6,400	$ 10,300

Restructuring Charges, Foreign Exchange and Other

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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

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-Publisher FASB
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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

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
-SubTopic 10
-Section 50
-Paragraph 1
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+ References

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