Restructuring and Related Activities - Restructuring Reserves (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Reserve [Roll Forward]
Beginning balance		$ 15,211	$ 2,025
Accruals for voluntary and involuntary termination benefits			15,645
Accruals for lease terminations			7,117
Payments			(9,576)
Ending balance			15,211
Employee Severance
Restructuring Reserve [Roll Forward]
Beginning balance	$ 1,085
Accruals for voluntary and involuntary termination benefits	15,645
Accruals for lease terminations	0
Payments	(7,511)
Ending balance	9,219	1,085
Lease Termination Charges
Restructuring Reserve [Roll Forward]
Beginning balance	$ 5,992	940
Accruals for voluntary and involuntary termination benefits		0
Accruals for lease terminations		7,117
Payments		(2,065)
Ending balance		$ 5,992	$ 940

Restructuring Reserve, Accrual Adjustment, Contract Termination

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- Definition

Restructuring Reserve, Accrual Adjustments, Termination Benefits

+ References

No definition available.

+ Details

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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
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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