Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Notes Tables
Notes Details

Basis of Presentation - Evaluation of Ability to Maintain Current Level of Operations (Details)

v3.20.4

Basis of Presentation - Evaluation of Ability to Maintain Current Level of Operations (Details) $ in Thousands				3 Months Ended						9 Months Ended
	Sep. 28, 2020	Jun. 01, 2020 employee	Mar. 23, 2020 company employee MW	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2020 USD ($)
Basis of Presentation
Net loss				$ (7,595)	$ (4,212)	$ (1,823)	$ (4,907)	$ (4,448)	$ (5,593)	$ (13,630)	$ (14,948)
Cash received (used) in operating activities										(3,366)	$ (15,720)
Cash and cash equivalents				31,970						31,970		$ 15,068
Long-term debt				$ 52,900						$ 52,900
Business Continuity Plan, Number of Employees Furloughed \| employee			52
Business Continuity Plan, Threshold Furloughed Period			45 days
Percentage of Salary Cut Volunteered by Leadership Team			25.00%
Number of Other Top Company Mangers Volunteered for Salary Cut \| company			25
Percentage of Salary Cut Volunteered by Several Employees			15.00%
Percentage of Salary Cut Volunteered by Other Top Managers			15.00%
Percentage of Temporary Reduction in Base Cash Retainer			25.00%
Number of Employees Eliminated \| employee		26
Capacity of Pre Built Microturbine Finished Goods \| MW			5.9
Percentage of salary after business continuity plan	100.00%

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