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Class Of Warrant Or Right, Warrants Issued, Price Per Share

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Offering Costs

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Payments For Clearing Fees

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Payments For Placement Agent Commissions

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Payments Related To Expenses For Registered Direct Offering And Concurrent Private Placement

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- Definition

Proceeds from the Issuance of Common Stock and Warrants, Net of Issuance Costs

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Standard Product Warranty, Number of Years

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

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

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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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- Definition

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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- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

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The cash outflow for a borrowing supported by a written promise to pay an obligation.

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Value of preferred stock and warrants for common stock issued.

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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended			6 Months Ended		12 Months Ended
	Nov. 29, 2019	Jan. 31, 2020	Oct. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2016	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Concentration Risk [Line Items]
Securities excluded from net loss per share calculation (in shares)				47,000	28,000		4,000	66,000
Sale of common stock (in shares)							721,546
Exercise price of common stock (in dollars per share)				$ 3.48			$ 3.48
Proceeds from issuance of warrants							$ 2,500
Issuance of warrants, January 2020		$ 1,636		$ 103			15
Proceeds from the exercise of warrants							51	$ 0
Amount paid for clearing fees		231
Offering costs		474
Proceeds from sale of common stock		$ 2,300
Percentage of gross proceeds used to make payments on note		10.00%
Gross proceeds		$ 275
Payments on the Iliad Note							$ 526	$ 0
Note Purchase Agreement
Concentration Risk [Line Items]
Percentage of gross proceeds used to make payments on note	10.00%
Payments on the Iliad Note		$ 226
Institutional Investor
Concentration Risk [Line Items]
Sale of common stock (in shares)		688,360		673,361
Exercise price of common stock (in dollars per share)				$ 3.37			$ 3.37
Purchase price (in usd per share)		$ 0.625
Private Placement
Concentration Risk [Line Items]
Sale of common stock (in shares)				48,185			48,185
Exercise price of common stock (in dollars per share)				$ 4.9940			$ 4.9940
Amount paid for placement agent commissions		$ 193
Amount paid related to expenses for registered direct offering and concurrent private placement		$ 50
All Other Products
Concentration Risk [Line Items]
Warranty service periods			5 years
LEDFL Tubular LED Lamps (Excluding Red Caps)
Concentration Risk [Line Items]
Warranty service periods			10 years
Minimum
Concentration Risk [Line Items]
Warranty service periods						1 year
Maximum
Concentration Risk [Line Items]
Warranty service periods						5 years
Maximum \| Commercial LEDFL Tubular LED Lamps (Excluding Battery Backup TLED), Troffer Luminaires, And Certain Globe Lights
Concentration Risk [Line Items]
Warranty service periods						10 years
Customer concentration risk
Concentration Risk [Line Items]
Concentration risk (less than for one percent)				10.00%			10.00%
Customer concentration risk \| Revenue \| Distributor To The U.S. Navy
Concentration Risk [Line Items]
Concentration risk (less than for one percent)				40.00%	13.00%		39.00%	17.00%
Customer concentration risk \| Revenue \| Distributor for the U.S. Navy and a Regional Commercial Lighting Retrofit Company
Concentration Risk [Line Items]
Concentration risk (less than for one percent)				15.00%	26.00%		15.00%	28.00%
Customer concentration risk \| Revenue \| U.S. Navy and Shipbuilders
Concentration Risk [Line Items]
Concentration risk (less than for one percent)				11.00%	20.00%		53.00%	26.00%
Customer concentration risk \| Revenue \| Distributor To The U.S. Navy Combined With Sales To Shipbuilders
Concentration Risk [Line Items]
Concentration risk (less than for one percent)				60.00%
Customer concentration risk \| Accounts receivable \| Distributor To The U.S. Navy
Concentration Risk [Line Items]
Concentration risk (less than for one percent)							47.00%		10.00%
Customer concentration risk \| Accounts receivable \| Distributor for the U.S. Navy and a Regional Commercial Lighting Retrofit Company
Concentration Risk [Line Items]
Concentration risk (less than for one percent)							19.00%		41.00%
Geographic concentration risk \| Revenue \| Countries outside of the United States
Concentration Risk [Line Items]
Concentration risk (less than for one percent)				1.00%	0.00%		1.00%	1.00%