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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) - USD ($) shares in Thousands, $ in Thousands			3 Months Ended		12 Months Ended
	Apr. 01, 2016	Feb. 27, 2012	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Concentration Risk [Line Items]
Securities excluded from net loss per share calculation (in shares)			219
Interest expense			$ 0	$ 23
Communal
Concentration Risk [Line Items]
Recorded expenses under agreement				$ 56
Chief Executive Officer
Concentration Risk [Line Items]
Ownership interest		50.00%
Subsequent event
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
Immediate family member of management
Concentration Risk [Line Items]
Ownership interest		50.00%
Geographic concentration risk | United States
Concentration Risk [Line Items]
Concentration risk, percentage			99.00%
Revenue | Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage			12.00%
Revenue | Customer concentration risk | LED Lighting Solutions Global, LLC
Concentration Risk [Line Items]
Concentration risk, percentage				86.00%
Revenue | Product concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage			39.00%
Revenue | Geographic concentration risk | Countries outside of the United States
Concentration Risk [Line Items]
Concentration risk, percentage			6.00%	1.00%
Accounts receivable | Customer concentration risk | LED Lighting Solutions Global, LLC
Concentration Risk [Line Items]
Concentration risk, percentage			11.00%
DFAS Columbus | Revenue | Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage			20.00%
DFAS Columbus | Accounts receivable | Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage			27.00%
Atlantic Diving Supply, Inc. | Revenue | Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage			19.00%
Atlantic Diving Supply, Inc. | Accounts receivable | Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage			21.00%		62.00%
Global Energy Services, LLC | Accounts receivable | Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage			12.00%

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