Line of credit facility additional availability upon achievement of trailing twelve month revenues.

No definition available.

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- Definition

Line of credit facility amortization period upon extension of interest-only period.

+ References

No definition available.

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Line of credit facility amortization period without interest only period extension.

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No definition available.

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Line of credit facility increase in final payment fees percentage upon extension interest only periods.

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No definition available.

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- Definition

Line of credit facility interest-only period.

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- Definition

Line of credit facility interest only period extension period upon achievement of revenues.

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No definition available.

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Line of credit facility interest only period extension upon achievement of revenues.

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No definition available.

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- Definition

Line of credit facility percentage of forecasted revenue to be achieved in financial maintenance covenant.

+ References

No definition available.

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- Definition

Line of credit facility prepayment fees percentage.

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No definition available.

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- Definition

The floor interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

No definition available.

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- Definition

Notification period to lenders in order to borrow loan upon achieving required revenue milestone.

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No definition available.

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- Definition

Percentage of warrant issued to trance borrowed.

+ References

No definition available.

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- Definition

Trailing twelve month revenues to be achieved for borrowing additional availability under line of credit facility.

+ References

No definition available.

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- Definition

Warrants expiration period.

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No definition available.

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- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 230
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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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- 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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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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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.

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No definition available.

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- Definition

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

+ References

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- Definition

Aggregate amount of interest expense on all borrowings.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

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The effective interest rate at the end of the reporting period.

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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.

+ References

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Section 50
-Paragraph 2
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Debt - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands		3 Months Ended
	Jul. 02, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Feb. 28, 2017
Debt Instrument [Line Items]
Interest expense		$ 900,000	$ 900,000
Cash interest expense		700,000	700,000
Non-cash interest expense		$ 200,000	$ 200,000
$35.0 Million Credit Facility
Debt Instrument [Line Items]
Percentage of forecasted revenue to be achieved		75.00%
$35.0 Million Credit Facility \| Prepaid on or Before First Anniversary of Funding
Debt Instrument [Line Items]
Prepayment fees percentage		3.00%
$35.0 Million Credit Facility \| Prepaid After First and on or Before Second Anniversary of Funding
Debt Instrument [Line Items]
Prepayment fees percentage		2.00%
$35.0 Million Credit Facility \| Prepaid After Second Anniversary of Funding
Debt Instrument [Line Items]
Prepayment fees percentage		1.00%
$35.0 Million Credit Facility \| Oxford Finance LLC
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity						$ 35,000,000	$ 25,000,000
Borrowings outstanding under credit facility		$ 30,000,000
Available borrowing achievement of trailing twelve month revenues						45,000,000
Debt instrument, interest rate		8.15%
Warrants term		7 years
Percentage of borrowing capacity of tranche		3.95%
Borrowing capacity of tranche		$ 5,000,000
Credit facility maturity date		Mar. 01, 2022
$35.0 Million Credit Facility \| Oxford Finance LLC \| LIBOR
Debt Instrument [Line Items]
Debt instrument, description of variable rate basis		30-day U.S. LIBOR
Basis spread on variable rate		7.38%
$35.0 Million Credit Facility \| Term A Loan
Debt Instrument [Line Items]
Available borrowing achievement of trailing twelve month revenues				$ 45,000,000
Interest-only period		2019-03
Amortization period without interest-only period extension		36 months
Extension of interest-only period upon achievement of revenues		12 months
Interest-only period upon achievement of revenues		2020-03
Amortization period upon extension of interest-only period		24 months
Increase in final payment fees percentage upon extension interest only periods		8.50%
Effective interest rates		11.87%			10.70%
$35.0 Million Credit Facility \| Term A Loan \| Common Stock
Debt Instrument [Line Items]
Warrants to purchase shares	20,303
Warrants, exercise price	$ 9.73
Warrants expiration period	2024-03
$35.0 Million Credit Facility \| Term A Loan \| Oxford Finance LLC
Debt Instrument [Line Items]
Borrowings outstanding under credit facility						25,000,000
$35.0 Million Credit Facility \| Term B Loan
Debt Instrument [Line Items]
Available borrowing achievement of trailing twelve month revenues				$ 45,000
Interest-only period		2019-03
Amortization period without interest-only period extension		36 months
Extension of interest-only period upon achievement of revenues		12 months
Interest-only period upon achievement of revenues		2020-03
Amortization period upon extension of interest-only period		24 months
Increase in final payment fees percentage upon extension interest only periods		7.50%
Effective interest rates		12.14%			11.60%
$35.0 Million Credit Facility \| Term B Loan \| Common Stock
Debt Instrument [Line Items]
Warrants to purchase shares	20,303
Warrants, exercise price	$ 9.73
Warrants expiration period	2024-12
$35.0 Million Credit Facility \| Term B Loan \| Oxford Finance LLC
Debt Instrument [Line Items]
Borrowings outstanding under credit facility						5,000,000
$35.0 Million Credit Facility \| Term C Loan \| Oxford Finance LLC
Debt Instrument [Line Items]
Line of credit facility, current borrowing capacity						$ 5,000,000
Notification period for lenders to borrow loan upon achieving required revenue milestone		60 days
Line of credit facility additional borrowing capacity		$ 5,000,000