Goodwill and Intangible Assets - Schedule of Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 27, 2019	Oct. 28, 2018	Oct. 27, 2019	Oct. 28, 2018	Jan. 27, 2019
Finite-Lived Intangible Assets [Line Items]
2020 (remaining three months)	$ 3,700		$ 3,700
2021	7,978		7,978
2022	4,655		4,655
2023	3,714		3,714
2024	1,389		1,389
Thereafter	0		0
Total expected amortization expense	21,436		21,436		$ 34,258
Intangible amortization	3,770	$ 6,480	12,821	$ 19,921
Core technologies
Finite-Lived Intangible Assets [Line Items]
2020 (remaining three months)	3,267		3,267
2021	7,389		7,389
2022	4,655		4,655
2023	3,714		3,714
2024	1,389		1,389
Thereafter	0		0
Total expected amortization expense	20,414		20,414		31,386
Intangible amortization	3,337	5,047	10,971	15,622
Customer relationships
Finite-Lived Intangible Assets [Line Items]
2020 (remaining three months)	433		433
2021	589		589
2022	0		0
2023	0		0
2024	0		0
Thereafter	0		0
Total expected amortization expense	1,022		1,022		$ 2,872
Intangible amortization	$ 433	$ 1,433	$ 1,850	$ 4,299

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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