Components of Convertible Senior Notes (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument
Debt principal	$ 116,980	$ 459,971
Unamortized discount	8,554	49,860
Current debt	19,182	33,343
Long-term debt	89,244	376,768
Net carrying amount of convertible debt	$ 108,426	$ 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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