Description of Business	12 Months Ended
Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Mercury Systems, Inc. (the “Company” or “Mercury”) is a leading commercial provider of secure sensor and safety critical mission processing subsystems. Optimized for customer and mission success, its solutions power a wide variety of critical defense and intelligence programs. Headquartered in Andover, Massachusetts, it is pioneering a next-generation defense electronics business model specifically designed to meet the industry's current and emerging technology and business needs. The Company delivers affordable innovative solutions, rapid time-to-value and service and support primarily to defense prime contractor customers. The Company's products and solutions have been deployed in more than 300 programs with over 25 different defense prime contractors. Key programs include Aegis, Patriot, Surface Electronic Warfare Improvement Program (“SEWIP”), Gorgon Stare, Predator, F-35, Reaper, F-16 SABR, E2D Hawkeye, Paveway, Filthy Buzzard, PGK, ProVision, P1, and AIDEWS. The Company's organizational structure allows it to deliver capabilities that combine technology building blocks and deep domain expertise in the aerospace and defense sector. On February 1, 2018, the Company acquired Themis Computer ("Themis") on a cash-free, debt-free basis for a total purchase price of approximately $180,000, prior to net working capital and net debt adjustments. Based in Fremont, California, Themis is a leading designer, manufacturer and integrator of commercial, SWaP-optimized rugged servers, computers and storage systems for U.S. and international defense programs. The acquisition of Themis is consistent with the Company's strategy and will expand its position in the Command, Control, Communications, Computers, and Intelligence ("C4I") market. See Note C to consolidated financial statements. On July 3, 2017, the Company acquired Richland Technologies, LLC ("RTL") on a cash-free, debt-free basis for a total purchase price of $5,798. Based in Duluth, Georgia, RTL specializes in safety-critical and high integrity systems, software, and hardware development as well as safety-certification services for mission-critical applications. In addition, RTL is a leader in safety-certifiable embedded graphics software for commercial and military aerospace applications. See Note C to consolidated financial statements. On April 3, 2017, the Company acquired Delta Microwave, LLC (“Delta”) on a cash-free, debt-free basis for a total purchase price of $40,500. Based in Oxnard, California, Delta is a leading designer and manufacturer of high-value radio frequency ("RF"), microwave and millimeter wave sub-assemblies and components for the military, aerospace, and space markets. See Note C to consolidated financial statements. On November 4, 2016, the Company acquired CES Creative Electronic Systems, S.A. (“CES”) for a total purchase price of approximately $39,123, prior to net working capital and net debt adjustments. Based in Geneva, Switzerland, CES is a leading provider of embedded solutions for military and aerospace mission critical computing applications. CES specializes in the design, development and manufacture of safety-certifiable product and subsystems solutions including: primary flight control units, flight test computers, mission computers, command and control processors, graphics and video processing and avionics-certified Ethernet and input-output ("IO"). CES has decades of experience designing subsystems deployed in applications certified up to the highest levels of design assurance. CES products and solutions are used on platforms such as aerial refueling tankers and multi-mission aircraft, as well as several types of unmanned platforms. See Note C to consolidated financial statements. On May 2, 2016, the Company acquired the custom microelectronics, RF and microwave solutions, and embedded security operations of Microsemi Corporation (the “Carve-Out Business”), resulting in the entities comprising the Carve-Out Business becoming 100% owned direct or indirect subsidiaries of Mercury (the “Carve-Out Acquisition”). Under the terms of the Purchase Agreement, the Company paid $300,000 in cash on a cash-free, debt-free basis, prior to working capital and other post-closing adjustments.

Description of Business

Mercury Systems, Inc. (the “Company” or “Mercury”) is a leading commercial provider of secure sensor and safety critical mission processing subsystems. Optimized for customer and mission success, its solutions power a wide variety of critical defense and intelligence programs. Headquartered in Andover, Massachusetts, it is pioneering a next-generation defense electronics business model specifically designed to meet the industry's current and emerging technology and business needs. The Company delivers affordable innovative solutions, rapid time-to-value and service and support primarily to defense prime contractor customers. The Company's products and solutions have been deployed in more than 300 programs with over 25 different defense prime contractors. Key programs include Aegis, Patriot, Surface Electronic Warfare Improvement Program (“SEWIP”), Gorgon Stare, Predator, F-35, Reaper, F-16 SABR, E2D Hawkeye, Paveway, Filthy Buzzard, PGK, ProVision, P1, and AIDEWS. The Company's organizational structure allows it to deliver capabilities that combine technology building blocks and deep domain expertise in the aerospace and defense sector.

On February 1, 2018, the Company acquired Themis Computer ("Themis") on a cash-free, debt-free basis for a total purchase price of approximately $180,000, prior to net working capital and net debt adjustments. Based in Fremont, California, Themis is a leading designer, manufacturer and integrator of commercial, SWaP-optimized rugged servers, computers and storage systems for U.S. and international defense programs. The acquisition of Themis is consistent with the Company's strategy and will expand its position in the Command, Control, Communications, Computers, and Intelligence ("C4I") market. See Note C to consolidated financial statements.

On July 3, 2017, the Company acquired Richland Technologies, LLC ("RTL") on a cash-free, debt-free basis for a total purchase price of $5,798. Based in Duluth, Georgia, RTL specializes in safety-critical and high integrity systems, software, and hardware development as well as safety-certification services for mission-critical applications. In addition, RTL is a leader in safety-certifiable embedded graphics software for commercial and military aerospace applications. See Note C to consolidated financial statements.

On April 3, 2017, the Company acquired Delta Microwave, LLC (“Delta”) on a cash-free, debt-free basis for a total purchase price of $40,500. Based in Oxnard, California, Delta is a leading designer and manufacturer of high-value radio frequency ("RF"), microwave and millimeter wave sub-assemblies and components for the military, aerospace, and space markets. See Note C to consolidated financial statements.

On November 4, 2016, the Company acquired CES Creative Electronic Systems, S.A. (“CES”) for a total purchase price of approximately $39,123, prior to net working capital and net debt adjustments. Based in Geneva, Switzerland, CES is a leading provider of embedded solutions for military and aerospace mission critical computing applications. CES specializes in the design, development and manufacture of safety-certifiable product and subsystems solutions including: primary flight control units, flight test computers, mission computers, command and control processors, graphics and video processing and avionics-certified Ethernet and input-output ("IO"). CES has decades of experience designing subsystems deployed in applications certified up to the highest levels of design assurance. CES products and solutions are used on platforms such as aerial refueling tankers and multi-mission aircraft, as well as several types of unmanned platforms. See Note C to consolidated financial statements.

On May 2, 2016, the Company acquired the custom microelectronics, RF and microwave solutions, and embedded security operations of Microsemi Corporation (the “Carve-Out Business”), resulting in the entities comprising the Carve-Out Business becoming 100% owned direct or indirect subsidiaries of Mercury (the “Carve-Out Acquisition”). Under the terms of the Purchase Agreement, the Company paid $300,000 in cash on a cash-free, debt-free basis, prior to working capital and other post-closing adjustments.