Number of warrants or right exercisable.

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Represents the number of warrants that are exercisable upon a condition such as draw of Term B Loan.

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No definition available.

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Percentage of outstanding long-term debt or borrowing associated with any securities or credit agreement for which there has been a default in principal, interest, sinking fund, or redemption provisions, or any breach of covenant that existed at the end of the period and subsequently has not been cured.

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Represents the percentage of exit fee of the total principal payments.

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Represents the amount of exit fee of the total principal payments.

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The number of features of the debt instrument that contribute to the determination that the instrument contains embedded derivatives.

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Represents the prepayment rate if prepayment occurs after the fourth anniversary.

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Represents the prepayment rate if prepayment occurs on or after the third anniversary.

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Represents the prepayment rate if prepayment occurs on or after the second anniversary of the applicable date of issuance but prior to the third anniversary.

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Represents the present value of prepayment rate if prepayment occurs prior to the second anniversary.

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The amount of fair value of warrants.

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Cash and cash equivalents required to maintain as the conditions for borrowing under the credit facility including the nature of any restrictions.

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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

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The average effective interest rate during the reporting period.

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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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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The effective interest rate during the reporting period.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Debt - Athyrium Credit Facility (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Oct. 01, 2018 USD ($) item $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares
Debt instruments
Number of features of embedded derivative \| item	2
Number of derivatives \| item	1
Restricted cash		$ 10,000	$ 10,000
Warrant exercisable \| shares		248,505	297,988
Interest expense		$ 8,589	$ 8,480
Warrants 2018
Debt instruments
Exercise Price \| $ / shares		$ 12.18
Warrant exercisable \| shares		184,660	184,660
Athyrium Credit Facility
Debt instruments
Aggregate principal amount		$ 75,000	$ 75,000
Cumulative accretion of exit fee		331	183
Debt issuance costs		3,088	3,999
Interest expense		8,440	8,316
Amortization of debt discount		910	807
Contractual coupon interest		$ 7,530	$ 7,509
Athyrium \| Athyrium Credit Facility
Debt instruments
Aggregate principal amount	$ 110,000
Debt term (in years)	6 years
Effective interest rate		11.63%
Athyrium \| Athyrium Credit Facility \| Warrants 2018
Debt instruments
Warrant to purchase shares of common stock \| shares	270,835
Exercise Price \| $ / shares	$ 12.18456
Warrant exercisable \| shares	184,660
Remaining warrant exercisable upon condition \| shares	86,175
Initial fair value of the Warrant	$ 1,900
Unamortized discount	1,980
Athyrium \| Term Loan A
Debt instruments
Aggregate principal amount	$ 75,000
Line of Credit Facility, Interest Rate During Period	9.875%
Exit fee of the total principal payments (as a percent)	1.00%
Cumulative accretion of exit fee	$ 750
Present value of prepayments if prepayment occurs prior to the second anniversary (as a percent)	105.00%
Prepayments if prepayment occurs on or after the second anniversary of the applicable date of issuance but prior to the third anniversary (as a percent)	3.00%
Prepayments if prepayment occurs on or after the third anniversary (as a percent)	2.00%
Prepayments if prepayment occurs after the fourth anniversary (as a percent)	0.00%
Additional interest rate upon an event of default accrued (as a percent)	3.00%
Total interest rate (as a percent)	12.875%
Financial covenant amount	$ 10,000
Athyrium \| Term Loan B
Debt instruments
Aggregate principal amount	$ 35,000