Restructuring Charges - Restructuring Costs Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Optimizing for Growth
Restructuring Reserve [Roll Forward]
Remaining liability at beginning of period	$ 17,635
Charges	12,901	$ 37,571
Payments/Utilization	(25,212)
Remaining liability at end of period	5,324	17,635
Optimizing for Growth \| Severance
Restructuring Reserve [Roll Forward]
Remaining liability at beginning of period	6,151
Charges	6,874
Payments/Utilization	(7,731)
Remaining liability at end of period	5,294	6,151
Optimizing for Growth \| Other restructuring costs
Restructuring Reserve [Roll Forward]
Remaining liability at beginning of period	11,484
Charges	6,027
Payments/Utilization	(17,481)
Remaining liability at end of period	30	11,484
Restructuring Plan, Other \| Severance
Restructuring Reserve [Roll Forward]
Remaining liability at beginning of period	0
Charges	18,600
Payments/Utilization	(12,675)
Remaining liability at end of period	$ 5,925	$ 0

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585

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- Definition

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

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-Publisher FASB
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
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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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