Operating Leases and Other Commitments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012
Future minimum payments required under non-cancellable leases
Leases, 2013	$ 27,112
Leases, 2014	22,869
Leases, 2015	18,205
Leases, 2016	12,583
Leases, 2017	8,231
Leases, thereafter	10,040
Leases, total	99,040
Less - Sublease Income, 2013	(330)
Less - Sublease Income, 2014	(238)
Less - Sublease Income, 2015	(196)
Less - Sublease Income, 2016	(152)
Less - Sublease Income, 2017	(95)
Less - Sublease Income, thereafter	(79)
Less - Sublease Income, total	(1,090)
Net, 2013	26,782
Net, 2014	22,631
Net, 2015	18,009
Net, 2016	12,431
Net, 2017	8,136
Net, thereafter	9,961
Net, Total	$ 97,950

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The total of future contractually required net payments on leases defined as operating.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required net rental payments due within one year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required net rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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Namespace Prefix:	mnro_
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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required net rental payments due within the fourth year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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Namespace Prefix:	mnro_
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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required net rental payments due within the third year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

Name:	mnro_OperatingLeasesFutureMinimumPaymentsNetDueInThreeYears
Namespace Prefix:	mnro_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required net rental payments due within the second year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

Name:	mnro_OperatingLeasesFutureMinimumPaymentsNetDueInTwoYears
Namespace Prefix:	mnro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required net rental payments due after the fifth year from the balance sheet date on leases defined as operating.

+ References

No definition available.

+ Details

Name:	mnro_OperatingLeasesFutureMinimumPaymentsNetDueThereafter
Namespace Prefix:	mnro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents the total aggregate minimum sublease rentals, if any, to be received under noncancelable subleases existing as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 98

-Paragraph 18

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6456377&loc=d3e50824-112756

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases after the fifth year following the balance sheet date.

+ References

+ Details

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- Definition

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the fifth year following the balance sheet date.

+ References

+ Details

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- Definition

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the fourth year following the balance sheet date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within one year of the balance sheet date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the third year following the balance sheet date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the second year following the balance sheet date.

+ References

+ Details

Name:	us-gaap_FutureMinimumSubleaseRentalsSaleLeasebackTransactionsWithinTwoYears
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total of future contractually required payments on leases defined as operating.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph b(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

+ Details

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Period Type:	instant

- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within one year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fourth year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the third year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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Period Type:	instant

- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the second year of the balance sheet date relating to leases defined as operating.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due after the fifth year from the balance sheet date on leases defined as operating.

+ References

+ Details

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