Subsequent Events	12 Months Ended
Sep. 30, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn December 13, 2022, EMCORE Chicago consummated the sale of the real property interests in the Tinley Park Facility to the Tinley Park Buyer, resulting in net proceeds of approximately $10.3 million, pursuant to the terms of the Tinley Park Purchase Agreement. In connection with the sale of the real property interests in the Tinley Park Facility, we entered into the Lease Agreement with the Tinley Park Buyer pursuant to which we leased back the Tinley Park Facility for a 12 year term commencing on December 13, 2022, unless earlier terminated or extended in accordance with the terms of the Lease Agreement.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI https://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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