Promissory Notes (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Principal amount	$ 15,595	$ 26,932
Carrying amount	12,783	14,653
Long-term Note	$ 15,135
Advantech Capital Investment II Limited
Short-term Debt [Line Items]
Interest rate	8.00%
Principal amount	$ 12,000	12,000
Carrying amount	9,033	3,193
Convertible Note
Short-term Debt [Line Items]
Short-term Note	$ (12,783)	(8,013)
Long-term Note		6,640
Convertible Note \| Mr.McMahon
Short-term Debt [Line Items]
Interest rate	4.00%
Principal amount		3,000
Carrying amount		3,260
Convertible Note With Maturity February 8, 2020 \| SSSIG
Short-term Debt [Line Items]
Interest rate	4.00%
Principal amount		1,252
Carrying amount		1,301
Convertible Note With Maturity November 25, 2020 \| SSSIG
Short-term Debt [Line Items]
Interest rate	4.00%
Principal amount		250
Carrying amount		250
Senior Secured Convertible Note (b)
Short-term Debt [Line Items]
Interest rate	10.00%
Principal amount		850
Carrying amount		348
Senior Secured Convertible Note (c)
Short-term Debt [Line Items]
Interest rate	10.00%
Principal amount		3,580
Carrying amount		1,896
Senior Secured Convertible Note (d)
Short-term Debt [Line Items]
Interest rate	4.00%
Principal amount		3,000
Carrying amount		1,405
Promissory Note
Short-term Debt [Line Items]
Interest rate	6.00%
Principal amount	$ 3,000	3,000
Carrying amount	3,153	3,000
Vendor Notes Payable
Short-term Debt [Line Items]
Principal amount	135
Carrying amount	$ 135	0
Vendor Notes Payable \| Minimum
Short-term Debt [Line Items]
Interest rate	0.25%
Small Business Association Paycheck Protection Program
Short-term Debt [Line Items]
Interest rate	1.00%
Principal amount	$ 460
Carrying amount	$ 462	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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