DOCUMENT AND ENTITY INFORMATION - Jun. 30, 2015 - shares	Total
Document and Entity Information [Abstract]
Entity Registrant Name	MERITOR INC
Entity Central Index Key	0001113256
Current Fiscal Year End Date	--09-30
Entity Filer Category	Large Accelerated Filer
Trading Symbol	MTOR
Entity Common Stock, Shares Outstanding	96,551,713
Document Period End Date	Jun. 30, 2015
Document Type	10-Q
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2015
Amendment Flag	false