Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Oct. 27, 2018	Jan. 27, 2018
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 867,835	$ 760,312
Less: current portion	0	(26,469)
Long-term debt	867,835	733,843
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt and capital lease obligations	$ 417,835	402,249
Debt, interest rate (in percent)	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	$ 450,000	$ 358,063

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)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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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 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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-SubTopic 10
-Section S99
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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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