Name:	m_DefinedBenefitPlanExpectedFutureFedearlSubsidyInFiveFiscalYearsThereafter
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The amount of subsidy expected to be received in Year 5.

No definition available.

Name:	m_DefinedBenefitPlanExpectedFutureFederalSubsidyInYearFive
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of subsidy expected to be received in Year 4.

No definition available.

Name:	m_DefinedBenefitPlanExpectedFutureFederalSubsidyInYearFour
Namespace Prefix:	m_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of the subsidy expected to be received in Year 1.

No definition available.

Name:	m_DefinedBenefitPlanExpectedFutureFederalSubsidyInYearOne
Namespace Prefix:	m_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of subsidy expected to be received in Year 3.

No definition available.

Name:	m_DefinedBenefitPlanExpectedFutureFederalSubsidyInYearThree
Namespace Prefix:	m_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of subsidy expected to be received in Year 2.

No definition available.

Name:	m_DefinedBenefitPlanExpectedFutureFederalSubsidyInYearTwo
Namespace Prefix:	m_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	m_ExpectedBenefitAbstract
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Period Type:	duration

- Details

Name:	m_ExpectedFederalSubsidyAbstract
Namespace Prefix:	m_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
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Period Type:	instant

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.