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Represents the default period in the payment when due of interest on any note to invoke customary default provisions under the convertible notes.

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Threshold amount of money to be borrowed to invoke customary default provisions under the convertible notes.

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Amount of excess of issue price over par or stated value of stock and from other transaction involving stock or stockholder. Includes, but is not limited to, additional paid-in capital (APIC) for common and preferred stock.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. 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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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Convertible Senior Notes - Convertible Senior Notes (Details) $ / shares in Units, $ in Thousands		3 Months Ended
	Feb. 13, 2020 USD ($) D $ / shares	Mar. 31, 2022 USD ($) D	Dec. 31, 2021 USD ($)
Debt
Convertible senior notes \| $		$ 140,189	$ 139,966
Accumulated deficit \| $		(269,411)	(256,342)
Additional paid-in capital \| $		513,312	$ 502,095
Convertible senior notes
Debt
Interest rate (as a percent)	2.625%
Aggregate principal amount \| $	$ 143,750
Initial conversion rate	34.2618
Initial conversion price \| $ / shares	$ 29.19
Conversion, threshold percentage of stock price trigger	130.00%
Conversion, threshold trading days \| D	20
Conversion, threshold consecutive trading days \| D	30
Consecutive business days \| D	5
Measurement period \| D	10
Threshold percentage to product of sale price of common stock and conversion rate	98.00%
Default period	30 days
Threshold amount of money borrowed \| $	$ 20,000
Convertible senior notes \| $		$ 140,189
Convertible senior notes \| Conversion of convertible debt after the calendar quarter ending on March 31, 2020
Debt
Conversion, threshold percentage of stock price trigger		130.00%
Conversion, threshold trading days \| D		20
Conversion, threshold consecutive trading days \| D		30