Income Taxes (Details Texuals) (USD $) In Millions, unless otherwise specified	6 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Net Pre Tax Losses Tax Benefitis Not Recorded	$ 52	$ 85

Net pre-tax losses for which a tax benefit is not recorded.

No definition available.

Name:	mtor_NetPreTaxLossesTaxBenefitisNotRecorded
Namespace Prefix:	mtor_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration