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Debt instrument convertible conversion price percentage.

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Long-term Debt, Percentage In Aggregate Principal Amount

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Number of additional tranches.

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Percentage of exit fee on amount borrowed on final repayment.

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Percentage of prepayment fee.

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Percentage of repurchase price is equal to principal amount of convertible notes

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Amount of amortization expense attributable to debt issuance costs.

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The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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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 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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The cash inflow from the issuance of a long-term debt 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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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Indebtedness - Additional Information (Details)			9 Months Ended
Indebtedness - Additional Information (Details)	May 21, 2020 USD ($) day $ / shares	May 02, 2019 USD ($) Tranche	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Debt Instrument [Line Items]
Amount funded			$ 0	$ 28,222,000
Proceeds from issuance of convertible debt, net			193,596,000	$ 0
Term Loan \| Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 150,000,000.0
Amount funded		30,000,000.0
Remaining borrowing capacity		$ 120,000,000.0
Number of additional tranches \| Tranche		2
Percentage of exit fee on amount borrowed on final repayment		1.75%
Percentage of exit fee on amount borrowed on partial prepayment		1.75%
Debt covenant minimum unrestricted cash percentage		25.00%
Debt instrument, default trigger amount			$ 2,500,000
Term Loan \| Credit Facility \| Prepayment Occurs through First Anniversary of Closing Date
Debt Instrument [Line Items]
Percentage of prepayment fee		3.00%
Term Loan \| Credit Facility \| First Anniversary of Closing Date through Second Anniversary of Closing Date
Debt Instrument [Line Items]
Percentage of prepayment fee		2.00%
Term Loan \| Credit Facility \| Second Anniversary of Closing Date and Prior to Jan 1, 2025
Debt Instrument [Line Items]
Percentage of prepayment fee		1.00%
Term Loan \| Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		7.00%
Interest rate		2.00%
Term Loan \| Credit Facility \| MidCap Financial Trust
Debt Instrument [Line Items]
Basis spread on variable rate			3.00%
Term Loan \| Tranche One \| Credit Facility
Debt Instrument [Line Items]
Remaining borrowing capacity		$ 60,000,000.0
Term Loan \| Tranche Two \| Credit Facility
Debt Instrument [Line Items]
Remaining borrowing capacity		$ 60,000,000.0
2027 Notes
Debt Instrument [Line Items]
Interest rate	5.00%		5.00%
Debt instrument aggregate principal amount	$ 200,000,000.0
Proceeds from issuance of convertible debt, net	$ 193,600,000
Convertible notes, initial conversion price (in dollars per share) \| $ / shares	$ 16.23
Debt instrument conversion ratio	0.0616
Convertible notes, percentage of conversion price	130.00%
Debt conversion, converted Instrument	$ 1,000
Convertible notes, redemption percentage	100.00%
Percentage of repurchase price is equal to principal amount of convertible notes	100.00%
Percentage in aggregate principal amount (not less than)	0.25
Carrying amount of the equity component	$ 53,000,000.0
Convertible notes, effective interest rate	11.17%
Debt issuance costs	$ 400,000
Amortization of debt issuance cost	$ 300,000
2027 Notes \| Maximum
Debt Instrument [Line Items]
Convertible notes, percentage of last reported sale price of common stock	98.00%
2027 Notes \| 130% Applicable Conversion Price \| Minimum
Debt Instrument [Line Items]
Convertible notes, consecutive trading days \| day	20
2027 Notes \| 130% Applicable Conversion Price \| Maximum
Debt Instrument [Line Items]
Convertible notes, consecutive trading days \| day	30
2027 Notes \| 98% Applicable Conversion Price \| Minimum
Debt Instrument [Line Items]
Convertible notes, consecutive trading days \| day	5
2027 Notes \| 98% Applicable Conversion Price \| Maximum
Debt Instrument [Line Items]
Convertible notes, consecutive trading days \| day	10