Restructuring - Restructuring Reserve Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2021	Jan. 26, 2020	Jan. 27, 2019
Restructuring Reserve [Roll Forward]
Beginning balance	$ 238	$ 1,009	$ 4,749
Charges (recoveries)	(238)	2,166	695
Cash payments		(2,937)	(4,435)
Ending balance	0	238	1,009
One-time employee termination benefits
Restructuring Reserve [Roll Forward]
Beginning balance	114	720	4,063
Charges (recoveries)	(114)	1,483	695
Cash payments		(2,089)	(4,038)
Ending balance	0	114	720
Contract commitments
Restructuring Reserve [Roll Forward]
Beginning balance	124	289	686
Charges (recoveries)	(124)	683	0
Cash payments		(848)	(397)
Ending balance	$ 0	$ 124	$ 289

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
-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

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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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

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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.

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