NATURE OF THE BUSINESS AND OPERATIONS	12 Months Ended
NATURE OF THE BUSINESS AND OPERATIONS	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
NATURE OF THE BUSINESS AND OPERATIONS	NATURE OF THE BUSINESS AND OPERATIONS Acacia Communications, Inc. was incorporated on June 2, 2009, as a Delaware corporation. Acacia Communications, Inc. and its wholly owned subsidiaries (the “Subsidiaries”) are collectively referred to as the Company. The Company’s mission is to deliver high-speed coherent optical interconnect products that transform communications networks relied upon by cloud infrastructure operators and content and communication service providers, through improvements in performance and capacity and reductions in associated costs. By implementing optical interconnect technology in a silicon-based platform, a process the Company refers to as the siliconization of optical interconnect, the Company believes it is leading a disruption that is analogous to the computing industry’s integration of multiple functions into a microprocessor. The Company's products fall into three product groups: embedded modules, pluggable modules and semiconductors. The Company's embedded module and pluggable module product groups consist of optical interconnect modules with transmission speeds ranging from 100 to 1,200 gigabits per second (“Gbps”) for use in long-haul, metro and inter-data center markets. The Company's semiconductor product group consists of its low-power coherent digital signal processor application-specific integrated circuits (“DSP ASICs”) and its silicon photonic integrated circuits (“silicon PICs”) which are either integrated into the Company's embedded and pluggable modules or sold to customers on a standalone basis for integration into internally developed or other merchant modules. The Company’s modules perform a majority of the digital signal processing and optical functions in optical interconnects and offer low power consumption, high density and high speeds at attractive price points. Through the use of standard interfaces, the Company’s modules can be easily integrated with customers’ network equipment. The advanced software in the Company’s modules enables increased configurability and automation, provides insight into network and connection point characteristics and helps identify network performance problems, all of which increase flexibility and reduce operating costs. The Company is headquartered in Maynard, Massachusetts, and has wholly owned subsidiaries in North America, Europe and Asia. Merger with Cisco Systems On July 8, 2019, the Company, Cisco Systems, Inc., a California corporation (“Parent”), and Amarone Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of Parent (“Merger Sub”), entered into an Agreement and Plan of Merger (the “Original Merger Agreement”). On January 14, 2021, the Company, Parent and Merger Sub entered into an Amended and Restated Agreement and Plan of Merger (the “Amended and Restated Merger Agreement”), which amended and restated the Original Merger Agreement in its entirety. The Amended and Restated Merger Agreement provided, subject to its terms and conditions, for the Company’s acquisition by Parent at a price of $115.00 per share of the Company’s common stock, $0.0001 par value per share (each a “Share”), in cash, without interest and subject to deduction for any required withholding tax (the “Merger Consideration”), through the merger of Merger Sub with and into the Company (the “Merger”), with the Company surviving the Merger as a wholly owned subsidiary of Parent. The Company’s Board of Directors unanimously approved the Merger and the Amended and Restated Merger Agreement and recommended that stockholders adopt the Amended and Restated Merger Agreement, and the Company’s stockholders adopted the Amended and Restated Merger Agreement at a special meeting held on March 1, 2021. The Merger was completed on March 1, 2021 following such special meeting. As of the effective time of the Merger, the Company became a wholly owned subsidiary of Parent and is no longer a publicly held corporation, its common stock will be delisted from The Nasdaq Global Select Market and deregistered under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and it will no longer be required to file periodic reports with the SEC. During the years ended December 31, 2020 and 2019, the Company recorded acquisition-related costs of $2.4 million and $7.6 million, respectively, in sales, general and administrative expenses within our consolidated income statements. Impact of COVID-19 An outbreak of the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (“SARS-CoV-2”), and the coronavirus disease, COVID-19, was identified in China in late 2019 and has spread globally. The Centers for Disease Control and Prevention has recognized this outbreak as a pandemic which has resulted in authorities imposing, and businesses and individuals implementing, numerous unprecedented measures to try to contain the virus, such as travel bans and restrictions, quarantines, shelter-in-place/stay-at-home and social distancing orders and shutdowns. These measures have impacted and may further impact the Company’s workforce and operations, the operations of the Company’s customers, and those of the Company’s and its customers’ respective vendors, suppliers and partners. While the COVID-19 pandemic did not have a material impact on the Company’s financial results for the year ended December 31, 2020, the extent to which the COVID-19 pandemic could impact the Company’s results of operations going forward depends on future developments that are highly uncertain and cannot be predicted, including the adverse impact of negative economic conditions created or exacerbated by the pandemic, new information that may emerge concerning the severity of the virus and required or voluntary actions to contain its impact. Due to the inherent uncertainty of this unprecedented and evolving situation, the Company is unable to predict with any confidence the likely impact of COVID-19 on its future business, results of operations and financial condition. Additional information regarding COVID-19 related risks and uncertainties may be found in the section titled “Risk Factors” under Part I, Item 1A in this Annual Report on Form 10-K.

Acacia Communications, Inc. 10-K