Description of Business	9 Months Ended
	Jun. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of BusinessEMCORE Corporation (referred to herein, together with its subsidiaries, as the “Company,” “we,” “our,” or “EMCORE”) is a leading provider of sensors for navigation in the aerospace and defense market as well as a manufacturer of lasers and optical subsystems for use in the broadband industry. We pioneered the linear fiber optic transmission technology that enabled the world’s first delivery of Cable TV (“CATV”) directly on fiber, and today are a leading provider of advanced products that enable communications systems and service providers to meet growing demand for increased bandwidth and connectivity. The technology at the heart of our broadband communications products is shared with our fiber optic gyroscope (“FOG”) and inertial sensors to provide the aerospace and defense markets with state-of-the-art navigation systems technology. With the acquisitions of (a) Systron Donner Inertial, Inc. (“SDI”), a navigation systems provider with a scalable, chip-based platform for higher volume gyro applications utilizing quartz micro-electromechanical system (“QMEMS”) technology, in June 2019, and (b) the L3Harris Space and Navigation (“S&N”) business in April 2022, we further expanded our portfolio of gyros and inertial sensors with SDI’s QMEMS gyro and accelerometer technology and S&N's FOG and ring laser gyro (“RLG”) technology. We have fully vertically-integrated manufacturing capability through our indium phosphide (“InP”) compound semiconductor wafer fabrication facility at our headquarters in Alhambra, CA and through our QMEMS processing and sensor manufacturing facility in Concord, CA and our FOG and RLG manufacturing facility in Budd Lake, NJ. These facilities support our vertically-integrated manufacturing strategy for QMEMS, FOG, and RLG products for navigation systems, and, with respect to our Alhambra, CA facility, for our chip, laser, transmitter, and receiver products for broadband applications. With both analog and digital circuits on multiple chips, or even a single chip, the value of Mixed-Signal device solutions is often substantially greater than traditional digital applications and requires a specialized expertise held by us which is unique in the optics industry.