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v3.3.1.900

Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2013 | Mar. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2016 | Dec. 31, 2012
Concentration Risk [Line Items] |  |  |  |  |  |  |
Cash and cash equivalents | $ 1,890 |  | $ 34,640 | $ 7,435 | $ 1,890 |  | $ 788
Restricted cash held | 94 |  | 113 | 105 | 94 |  |
Cash held in escrow | 500 |  | 0 | 300 | 500 |  |
Inventory adjustments | 109 |  | 1,500 | 95 | 109 |  |
Deferred tax assets, operating loss carry-forwards | 3,989 |  | $ 5,384 | 6,871 | 3,989 |  |
Collateralized assets |  |  |  | $ 1,000 |  |  |
Impairment of assets held for sale | $ 608 |  |  |  |  |  |
Sale price of assets held for sale |  | $ 130 |  |  |  |  |
Antidilutive securities excluded from computation of earnings per share (number of shares) |  |  | 818,832 | 1,955,809 |  |  |
Advertising expense |  |  | $ 695 | $ 214 | $ 82 |  |
Customer concentration risk | Net sales |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  | 80.00% | 74.00% |  |  |
Customer concentration risk | Net sales | LED Lighting Solutions Global, LLC |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  | 59.00% | 64.00% |  |  |
Customer concentration risk | Net sales | Atlantic Diving Supply, Inc. |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  | 16.00% |  |  |  |
Customer concentration risk | Net sales | DFAS Columbus |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  |  | 10.00% | 30.00% |  |
Customer concentration risk | Net sales | Ohio Department of Development |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  |  |  | 10.00% |  |
Customer concentration risk | Accounts receivable | LED Lighting Solutions Global, LLC |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  |  | 55.00% |  |  |
Customer concentration risk | Accounts receivable | Atlantic Diving Supply, Inc. |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  | 62.00% |  |  |  |
Customer concentration risk | Accounts receivable | ES Entegral Solutions, Inc. |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  |  | 20.00% |  |  |
Customer concentration risk | Accounts receivable | Johnson Controls, Inc. |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk |  |  |  | 10.00% |  |  |
Minimum |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Property and equipment, useful life |  |  | 2 years |  |  |  |
Standard Product Warranty, Number of Years |  |  | 1 year |  |  |  |
Maximum |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Property and equipment, useful life |  |  | 15 years |  |  |  |
Standard Product Warranty, Number of Years |  |  | 5 years |  |  |  |
Scenario, forecast |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Operating loss carry-forwards |  |  |  |  |  | $ 6,000 |
Domestic tax authority |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Operating loss carry-forwards |  |  | $ 69,100 |  |  |  |
Deferred tax assets, operating loss carry-forwards |  |  | $ 14,800 |  |  |  |

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