Debt - Summary of Components of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Amortization of debt issuance costs	$ 75	$ 140
Total	886	767
Warrants 1 and 2
Debt Instrument [Line Items]
Amortization of debt discount	77	367
Warrant 2
Debt Instrument [Line Items]
Mark to market of SWK Warrant 2 (defined below)	42	0
Term Loans \| Term Loans
Debt Instrument [Line Items]
Interest expense	349	138
Accretion of termination fees (over term of Term Loan at rate of 8%)	$ 111	$ 41
Effective interest rate percentage	28.00%	15.00%
Accretion of termination fees percentage	8.00%	8.00%
Line of Credit \| 2016 Credit and Security Agreement
Debt Instrument [Line Items]
Interest expense	$ 173	$ 81
Subordinated Debt \| Promissory Note
Debt Instrument [Line Items]
Interest expense	39	0
Amortization of debt discount	15	0
Capital Leases
Debt Instrument [Line Items]
Interest expense	$ 5	$ 0

Accretion Expense, Debt Discount Associated With Warrant

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- Definition

Accretion Expense, Termination Fees

+ References

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Debt Instrument, Termination Fee As A Percent Of Aggregate Principal Amount

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- Definition

Amount of amortization expense attributable to debt issuance costs.

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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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Amount of expense (income) related to adjustment to fair value of warrant liability.

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- Definition

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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