Debt instrument cap rate.

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- Definition

Debt Instrument, Covenant Terms, Potential Amortization Period Reduction

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No definition available.

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- Definition

Debt Instrument, Covenant Terms, Potential Maturity Term Reduction

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- Definition

Debt instrument facility fee paid.

+ References

No definition available.

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- Definition

Debt instrument floor rate.

+ References

No definition available.

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- Definition

Facility fee percentage paid on principal amount.

+ References

No definition available.

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- Definition

Line Of Credit Facility, First Quarter Periodic Payment, Principal, Term

+ References

No definition available.

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- Definition

Line Of Credit Facility, Maximum Borrowing Capacity, Number Of Available Tranches

+ References

No definition available.

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- Definition

Prepayment premium percentage on principal if prepaid on or after fourth anniversary of funding.

+ References

No definition available.

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- Definition

Prepayment premium percentage on principal if prepaid prior to fourth anniversary and after third anniversary of funding.

+ References

No definition available.

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- Definition

Prepayment premium percentage on principal if prepaid prior to third anniversary of funding

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

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

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- Definition

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.

+ References

No definition available.

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- Definition

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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- Definition

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

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Debt - Additional Information (Details)		3 Months Ended	9 Months Ended
Debt - Additional Information (Details)	Nov. 11, 2019 USD ($) tranche	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Nov. 25, 2019 USD ($)
Line of Credit Facility [Line Items]
Term loan, net of facility fees, lender expenses and issuance costs		$ 76,608,000	$ 76,608,000
Derivative liability		1,990,000	1,990,000	$ 1,650,000
Collateral Agent, Pharmakon
Line of Credit Facility [Line Items]
Derivative liability		2,000,000.0	2,000,000.0	$ 1,700,000
Biopharma Credit Investments V (Master) LP \| Keryx \| Term Loan \| Collateral Agent, Pharmakon
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 100,000,000.0
Line of credit, maximum borrowing capacity, number of available tranches \| tranche	2
Term loan, maturity term	5 years
Term loan, maturity term, potential reduction (up to)	1 year
Term loan, amortization period, potential reduction (up to)	1 year
Facility fee percentage on principal amount	2.00%
Facility fee paid, amount	$ 2,000,000.0
Prepayment premium percentage on principal if prepaid prior to third anniversary of funding	2.00%
Prepayment premium percentage on principal if prepaid prior to fourth anniversary and after third anniversary of funding	1.00%
Prepayment premium percentage on principal if prepaid after fourth anniversary of funding	0.50%
Interest expense		$ 2,200,000	$ 6,600,000
Biopharma Credit Investments V (Master) LP \| Keryx \| Term Loan \| Collateral Agent, Pharmakon \| Debt Instrument, Quarterly Periodic Payment, Period One
Line of Credit Facility [Line Items]
Term loan, first quarterly principal payment due in	33 months
Biopharma Credit Investments V (Master) LP \| Keryx \| Term Loan \| Collateral Agent, Pharmakon \| Debt Instrument, Quarterly Periodic Payment, Period Two
Line of Credit Facility [Line Items]
Term loan, first quarterly principal payment due in	48 months
Biopharma Credit Investments V (Master) LP \| Keryx \| Term Loan \| Collateral Agent, Pharmakon \| Three-month LIBOR
Line of Credit Facility [Line Items]
Basis spread on floating interest rate	7.50%
Biopharma Credit Investments V (Master) LP \| Keryx \| Term Loan \| Collateral Agent, Pharmakon \| LIBOR
Line of Credit Facility [Line Items]
Debt instrument, floor rate	2.00%
Debt instrument, cap rate	3.35%
Biopharma Credit Investments V (Master) LP \| Keryx \| Term Loan \| Collateral Agent, Pharmakon \| Tranche A
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 80,000,000.0
Term loan, net of facility fees, lender expenses and issuance costs					$ 77,300,000
Biopharma Credit Investments V (Master) LP \| Keryx \| Term Loan \| Collateral Agent, Pharmakon \| Tranche B
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 20,000,000.0