Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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Debt - Components of the Convertible Notes (Details) - USD ($)	Jan. 30, 2021	Jan. 25, 2020	Sep. 15, 2015
Estimate of Fair Value Measurement
Debt Instrument [Line Items]
Debt instrument, face amount	$ 60,886,000
Less: Debt discount and debt issuance costs	(1,854,000)
Net carrying amount of 2021 Convertible Notes	59,032,000
0.75% Convertible Senior Notes Due 2021
Debt Instrument [Line Items]
Debt instrument, face amount	58,264,000	$ 460,000,000	$ 485,000,000
Less: Debt discount	(1,665,000)
Less: Debt issuance costs	(189,000)
Net carrying amount of 2021 Convertible Notes	$ 56,410,000