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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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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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Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Jan. 31, 2019
Summary of Significant Accounting Policies Details [Line Items]
Derivative liability	$ 5,300
Revenue, net	23,166	$ 27,414
Assets	186,946		$ 206,905
Convertible Note 2019
Summary of Significant Accounting Policies Details [Line Items]
Restricted cash				$ 2,700
Domestic
Summary of Significant Accounting Policies Details [Line Items]
Revenue, net	5,600	9,700
Assets	146,400	135,500
Foreign
Summary of Significant Accounting Policies Details [Line Items]
Revenue, net	1,800	3,400
Assets	$ 40,500	$ 56,400
Sales Revenue
Summary of Significant Accounting Policies Details [Line Items]
Concentration risk	16.90%	48.00%
Sales Revenue \| Customer One
Summary of Significant Accounting Policies Details [Line Items]
Concentration risk		30.00%
Sales Revenue \| Customer Two
Summary of Significant Accounting Policies Details [Line Items]
Concentration risk		18.00%
Accounts Receivable
Summary of Significant Accounting Policies Details [Line Items]
Concentration risk	12.00%	37.00%
(Level 2) \| Estimate of Fair Value Measurement \| 2023 Term Loans
Summary of Significant Accounting Policies Details [Line Items]
Debt instrument, fair value disclosure	$ 24,800
(Level 2) \| Estimate of Fair Value Measurement \| Series B Senior Unsecured Convertible Notes
Summary of Significant Accounting Policies Details [Line Items]
Debt instrument, fair value disclosure	22,100
(Level 2) \| Reported Value Measurement \| 2023 Term Loans
Summary of Significant Accounting Policies Details [Line Items]
Debt instrument, fair value disclosure	53,900
(Level 3) \| Reported Value Measurement
Summary of Significant Accounting Policies Details [Line Items]
Derivative liability	$ 2,800