Nature of Operations	12 Months Ended
Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	NATURE OF OPERATIONS Energy Focus, Inc. and its subsidiary engage in the design, development, manufacturing, marketing, and sale of energy-efficient lighting systems. We operate in a single industry segment, developing and selling our energy-efficient light-emitting diode (“LED”) lighting products into the general commercial, industrial and military maritime markets. Our goal is to become a trusted leader in the LED lighting retrofit market by replacing fluorescent lamps in institutional buildings and high-intensity discharge (“HID”) lighting in low-bay and high-bay applications with our innovative, high-quality commercial and military tubular LED (“TLED”) products. Over the past few years we have exited non-core businesses to focus our efforts on TLED products, starting with the sale of our pool lighting products business in 2013. During 2015 we exited our turnkey solutions business operated by our subsidiary, Energy Focus LED Solutions, LLC (“EFLS”), and exited our United Kingdom business through the sale of Crescent Lighting Limited (“CLL”), our wholly-owned subsidiary. As a result, we have reclassified all net sales and expenses associated with both EFLS and CLL from the Consolidated Statements of Operations and have reported the related net income (loss) as discontinued operations. Please refer to Note 4, “Discontinued Operations,” for more information on our disposition of these businesses. Given the decline in our military maritime business, the changing competitive landscape of the U.S. Navy sales channel and the timing uncertainty of commercial sales growth, we implemented a restructuring initiative during the first quarter of 2017. The intent of the restructuring strategy was to maximize operating cost reductions without sacrificing either our new product pipeline or potential long-term revenue growth and return the Company to profitability. On February 19, 2017, the Board appointed Dr. Ted Tewksbury to serve as the Company’s Chairman of the Board, Chief Executive Officer and President to lead the Company’s restructuring efforts. Dr. Tewksbury, who holds M.S. and Ph.D. degrees in Electrical Engineering from MIT, is a well-seasoned semiconductor industry executive with experience in implementing and managing successful business restructurings. The restructuring initiative included an organizational consolidation of management functions in order to streamline and better align the Company into a more focused, efficient, and cost-effective organization. The initiative also included the transition from our historical direct sales model, to an agency driven sales channel strategy in order to expand our market presence throughout the U.S. During 2017 we closed our New York, New York, Arlington, Virginia and Rochester, Minnesota offices, reduced full-time equivalent headcount by 51 percent and significantly decreased operating expenses from 2016 levels (a net reduction of $8.4 million, which includes $1.8 million in offsetting restructuring and impairment charges). As of December 31, 2017, we had effectively transitioned our sales force to an agency driven sales channel, expanding our sales coverage to the entire U.S. through six geographic regions and 30 sales agents. As a result of this transition, we have substantially expanded from a primarily Midwest focus to build market presence and awareness in other regions of the U.S. with significant demand potential, including the Northeast, Southeast and California.

NATURE OF OPERATIONS

Energy Focus, Inc. and its subsidiary engage in the design, development, manufacturing, marketing, and sale of energy-efficient lighting systems. We operate in a single industry segment, developing and selling our energy-efficient light-emitting diode (“LED”) lighting products into the general commercial, industrial and military maritime markets. Our goal is to become a trusted leader in the LED lighting retrofit market by replacing fluorescent lamps in institutional buildings and high-intensity discharge (“HID”) lighting in low-bay and high-bay applications with our innovative, high-quality commercial and military tubular LED (“TLED”) products.

Over the past few years we have exited non-core businesses to focus our efforts on TLED products, starting with the sale of our pool lighting products business in 2013. During 2015 we exited our turnkey solutions business operated by our subsidiary, Energy Focus LED Solutions, LLC (“EFLS”), and exited our United Kingdom business through the sale of Crescent Lighting Limited (“CLL”), our wholly-owned subsidiary. As a result, we have reclassified all net sales and expenses associated with both EFLS and CLL from the Consolidated Statements of Operations and have reported the related net income (loss) as discontinued operations. Please refer to Note 4, “Discontinued Operations,” for more information on our disposition of these businesses.

Given the decline in our military maritime business, the changing competitive landscape of the U.S. Navy sales channel and the timing uncertainty of commercial sales growth, we implemented a restructuring initiative during the first quarter of 2017. The intent of the restructuring strategy was to maximize operating cost reductions without sacrificing either our new product pipeline or potential long-term revenue growth and return the Company to profitability. On February 19, 2017, the Board appointed Dr. Ted Tewksbury to serve as the Company’s Chairman of the Board, Chief Executive Officer and President to lead the Company’s restructuring efforts. Dr. Tewksbury, who holds M.S. and Ph.D. degrees in Electrical Engineering from MIT, is a well-seasoned semiconductor industry executive with experience in implementing and managing successful business restructurings.

The restructuring initiative included an organizational consolidation of management functions in order to streamline and better align the Company into a more focused, efficient, and cost-effective organization. The initiative also included the transition from our historical direct sales model, to an agency driven sales channel strategy in order to expand our market presence throughout the U.S. During 2017 we closed our New York, New York, Arlington, Virginia and Rochester, Minnesota offices, reduced full-time equivalent headcount by 51 percent and significantly decreased operating expenses from 2016 levels (a net reduction of $8.4 million, which includes $1.8 million in offsetting restructuring and impairment charges). As of December 31, 2017, we had effectively transitioned our sales force to an agency driven sales channel, expanding our sales coverage to the entire U.S. through six geographic regions and 30 sales agents. As a result of this transition, we have substantially expanded from a primarily Midwest focus to build market presence and awareness in other regions of the U.S. with significant demand potential, including the Northeast, Southeast and California.