Convertible Senior Notes - Summary of Net Carrying Amount of Liability Component of 2023 Notes (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Current portion of convertible senior notes, net	$ 14,156,000	$ 0
Convertible senior notes due 2023
Debt Instrument [Line Items]
Principal	101,787,000
Unamortized discount	(11,620,000)
Unamortized issuance cost	(1,015,000)
Net carrying amount	89,152,000
Current portion of convertible senior notes, net	$ 14,200,000

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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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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