Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Jan. 25, 2020	Jan. 26, 2019
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 866,901	$ 873,199
Less: current portion	(22,500)	(5,625)
Long-term debt	844,401	867,574
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 422,526	$ 423,199
Debt, interest rate (in percent)	0.75%	0.75%
Credit Agreement - Revolving facility (matures April 2020)
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 0	$ 0
Credit Agreement - Term Loan (matures April 2020)
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 444,375	$ 450,000

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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