Document and Entity Information - shares	9 Months Ended
	Jun. 30, 2015	Jul. 31, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	EMCORE CORPORATION
Entity Central Index Key	0000808326
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2015
Current Fiscal Year End Date	--09-30
Entity Filer Category	Accelerated Filer
Amendment Flag	false
Entity Common Stock, Shares Outstanding		25,563,888