Description of Business	12 Months Ended
Description of Business	Jul. 03, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Mercury Systems, Inc. (the “Company” or “Mercury”) is a leading technology company serving the aerospace and defense electronics industry, positioned at the intersection of high-tech and defense. Headquartered in Andover, Massachusetts, the Company delivers solutions that power a broad range of aerospace and defense programs, optimized for mission success in some of the most challenging and demanding environments. The Company envisions, creates and delivers innovative technology solutions purpose-built to meet our customers’ most-pressing high-tech needs, including those specific to the defense community. As a leading manufacturer of essential components, modules and subsystems, the Company sells to defense prime contractors, the U.S. government and original equipment manufacturers (“OEM”) commercial aerospace companies. The Company has built a trusted, contemporary portfolio of proven product solutions purpose-built for aerospace and defense that it believes meets and exceeds the performance needs of its defense and commercial customers. Customers add their own applications and algorithms to our specialized, secure and innovative pre-integrated solutions. This allows them to complete their full system by integrating with their platform, the sensor technology and, in some cases, the processing from Mercury, with their platform. The Company's products and solutions are deployed in more than 300 programs with over 25 different defense prime contractors and commercial aviation customers. The Company's transformational business model accelerates the process of making new technology profoundly more accessible to its customers by bridging the gap between commercial technology and aerospace and defense applications. The Company's long-standing deep relationships with leading high-tech companies, coupled with the Company's high level of research and development (“R&D”) investments and industry-leading trusted and secure design and manufacturing capabilities, are the foundational tenets of this highly successful model. The Company's capabilities, technology and R&D investment strategy combine to differentiate Mercury in its industry. The Company's technologies and capabilities include secure embedded processing modules and subsystems, mission computers, secure and rugged rack-mount servers, safety-critical avionics, radio frequency (“RF”) components, multi-function assemblies, subsystems and custom microelectronics. The Company maintains our technological edge by investing in critical capabilities and intellectual property (“IP” or “building blocks”) in processing and RF, leveraging open standards and open architectures to adapt quickly those building blocks into solutions for highly data-intensive applications, including emerging needs in areas such as artificial intelligence (“AI”). The Company's mission critical solutions are deployed by its customers for a variety of applications including command, control, communications, computers, intelligence, surveillance and reconnaissance (“C4ISR”), electronic intelligence, avionics, electro-optical/infrared (“EO/IR”), electronic warfare, weapons and missile defense, hypersonics and radar. On September 23, 2019, the Company acquired American Panel Corporation (“APC”) on a cash-free, debt-free basis for a total purchase price of $100,000, prior to net working capital and net debt adjustments. Based in Alpharetta, Georgia, APC is a leading innovator in large area display technology for the aerospace and defense market. APC's capabilities are deployed on a wide range of next-generation platforms. On May 20, 2019, the Company announced the commencement of an underwritten public offering of its common stock, par value $0.01 per share. On May 31, 2019 the Company closed the offering, including the full over-allotment allocation, selling an aggregate of 6,900 shares of common stock at a price to the public of $69.00 for total net proceeds of $454,343. On April 18, 2019, the Company acquired The Athena Group, Inc. (“Athena”) and Syntonic Microwave LLC (“Syntonic”) on a cash-free, debt-free basis for a combined total purchase price of $46,000, prior to net working capital and net debt adjustments. Athena was a privately-held company based in Gainesville, Florida and a leading provider of cryptographic and countermeasure IP vital to securing defense computing systems. Syntonic was a privately held company based in Campbell, California and a leading provider of advanced synthesizers, wideband phase coherent tuners and microwave converters optimized for signals intelligence and electronic intelligence applications demanding frequency coverage up to 40 GHz with 2 GHz instantaneous bandwidth. On January 29, 2019, the Company acquired GECO Avionics, LLC (“GECO”) on a cash-free, debt-free basis for a total purchase price of $36,500. Based in Mesa, Arizona, GECO has over twenty years of experience designing and manufacturing affordable safety-critical avionics and mission computing solutions. On July 31, 2018, the Company acquired Germane Systems, LC (“Germane”) on a cash-free, debt-free basis for a total purchase price of $45,000, prior to net working capital and net debt adjustments. Based in Chantilly, Virginia, Germane is an industry leader in the design, development and manufacturing of rugged servers, computers and storage systems for command, control and intelligence (“C2I”) applications. For further details on the acquisitions, see Note C to the consolidated financial statements.