Restructuring - Rollforward (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jul. 01, 2018
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	$ 6,310
Charges (Benefits)	1,788	$ 14,681
(Payments) Recoveries	(3,062)
Restructuring reserve, end	2,690
February 2018 Restructuring Plan:
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	5,449
Charges (Benefits)	1,842	10,833
(Payments) Recoveries	(2,853)
Restructuring reserve, end	2,092
Legacy Restructuring Plans
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	861
Charges (Benefits)	(54)	3,848
(Payments) Recoveries	(209)
Restructuring reserve, end	598
Non-cash impairment charges \| February 2018 Restructuring Plan:
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	0
Charges (Benefits)	2,346	0
(Payments) Recoveries	0
Restructuring reserve, end	0
Non-cash impairment charges \| Legacy Restructuring Plans
Restructuring Reserve [Roll Forward]
Charges (Benefits)	0	0
Severance and benefits \| February 2018 Restructuring Plan:
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	5,449
Charges (Benefits)	(382)	10,493
(Payments) Recoveries	(2,975)
Restructuring reserve, end	2,092
Severance and benefits \| Legacy Restructuring Plans
Restructuring Reserve [Roll Forward]
Charges (Benefits)	(3)	837
Other Restructuring \| February 2018 Restructuring Plan:
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning	0
Charges (Benefits)	(122)	340
(Payments) Recoveries	122
Restructuring reserve, end	0
Other Restructuring \| Legacy Restructuring Plans
Restructuring Reserve [Roll Forward]
Charges (Benefits)	$ (51)	$ 3,005

Payments (Recoveries) for Restructuring

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- Definition

Amount, after cash payment, 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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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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