Debt - Schedule of Carrying Value of Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total debt	$ 230,000	$ 260,000
Less: unamortized debt discount	29,616	37,190
Less: unamortized debt issuance costs	3,588	4,548
Less: current portion of other long-term debt		29,962
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total debt		30,000
Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Total debt	230,000	230,000
Less: current portion of convertible senior notes, net	$ 196,796	$ 188,300

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt classified as other, payable within one year or the operating cycle, if longer.

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