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- Definition

Debt Instrument Fee, Exit Fee

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Debt Instrument Fee, Upfront Fee

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- Definition

Debt Instrument, Interest Rate Floor

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- Definition

Interest Expense, Debt, Back End Fees

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- Definition

Number Of Trailing Quarters

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- Definition

Total Debt to Trailing Quarter Net Sales Ratio

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- Definition

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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- Definition

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

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- Definition

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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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Long-Term Debt - Narrative (Details)	3 Months Ended		4 Months Ended	9 Months Ended
Long-Term Debt - Narrative (Details)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Aug. 14, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 29, 2017 USD ($) quarter
Debt Instrument [Line Items]
Net product revenues	$ 1,902,000	$ 0		$ 4,042,000	$ 0
Debt amortization period				5 years 6 months
Interest expense, back end fees				$ 2,000,000
Debt issuance costs						$ 2,181,000
Senior Notes
Debt Instrument [Line Items]
Amortization of debt discount				1,000,000
Senior Notes \| Note Purchase Agreement
Debt Instrument [Line Items]
Unused borrowing capacity							$ 100,000,000
Face amount	$ 75,000,000			$ 75,000,000		$ 75,000,000
Stated interest rate	11.375%			11.375%			9.00%
Upfront fee							1.00%
Exit fee							2.00%
Interest expense, debt	$ 2,361,000			$ 6,855,000
Senior Notes \| Note Purchase Agreement \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Interest rate floor							1.00%
Senior Notes \| Note Purchase Agreement - Delayed Draw Notes
Debt Instrument [Line Items]
Unused borrowing capacity							$ 25,000,000
Number of trailing quarters \| quarter							4
Scenario, Forecast \| Senior Notes \| Note Purchase Agreement - Delayed Draw Notes
Debt Instrument [Line Items]
Net product revenues			$ 15,000,000
Total debt to trailing four quarter net revenues			6.50