Components of Convertible Senior Notes (Detail) - USD ($) $ in Thousands	Oct. 03, 2021	Dec. 31, 2020	Dec. 12, 2016
Debt Instrument
Current debt	$ 32,219	$ 33,343
Long-term debt	112,784	376,768
Net carrying amount of convertible debt	145,003	410,111
1.25% Convertible Senior Unsecured Notes Due December 15, 2023
Debt Instrument
Debt principal	157,972	459,971	$ 460,000
Unamortized discount	12,969	49,860
Net carrying amount of convertible debt	$ 145,003	$ 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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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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