Components of Convertible Senior Notes (Detail) - USD ($) $ in Thousands	Apr. 04, 2021	Dec. 31, 2020	Dec. 12, 2016
Debt Instrument
Current debt	$ 11,057	$ 33,343
Long-term debt	356,877	376,768
Net carrying amount of convertible debt	367,934	410,111
1.25% Convertible Senior Unsecured Notes Due December 15, 2023
Debt Instrument
Debt principal	408,695	459,971	$ 460,000
Unamortized discount	40,761	49,860
Net carrying amount of convertible debt	$ 367,934	$ 410,111

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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The portion of the carrying value of long-term convertible debt as of the balance sheet date that is scheduled to be repaid within one year or in the normal operating cycle if longer. Convertible debt is a financial instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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Face (par) amount of debt instrument at time of issuance.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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