Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_ChiefFinancialOfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=mei_SharebasedCompensationAwardTrancheFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=mei_SharebasedCompensationAwardTrancheFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=mei_ShareBasedCompensationAwardTrancheSixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

COMMON STOCK AND STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		60 Months Ended
	Oct. 29, 2016	Jul. 30, 2016	Oct. 31, 2015	Oct. 29, 2016	Oct. 31, 2015	May 02, 2020
Performance-Based Restricted Stock Awards (RSAs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 1.7		$ 0.0	$ 0.0	$ 0.4
Performance-Based Restricted Stock Awards (RSAs) \| Independent directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense				$ 1.0
Number of shares issued (in shares)		27,000
Performance-Based Restricted Stock Awards (RSAs) \| Forecast
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						5 years
Compensation expense						$ 24.8
Performance-Based Restricted Stock Awards (RSAs) \| 50% of Target Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent				50.00%
Number of RSAs earned based on performance (in shares)	411,000			411,000
Performance-Based Restricted Stock Awards (RSAs) \| 50% of Target Shares \| Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSAs earned based on performance (in shares)	24,000			24,000
Performance-Based Restricted Stock Awards (RSAs) \| 100% of Target Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent				100.00%
Number of RSAs earned based on performance (in shares)	822,000			822,000
Performance-Based Restricted Stock Awards (RSAs) \| 100% of Target Shares \| Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSAs earned based on performance (in shares)	48,000			48,000
Performance-Based Restricted Stock Awards (RSAs) \| 150% of Target Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent				150.00%
Number of RSAs earned based on performance (in shares)	1,233,000			1,233,000
Performance-Based Restricted Stock Awards (RSAs) \| 150% of Target Shares \| Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of RSAs earned based on performance (in shares)	72,000			72,000
Time-Based Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				5 years
Compensation expense	$ 1.6		$ 0.0	$ 0.0	$ 0.4
Awarded (in shares)				608,000
Time-Based Restricted Stock Units (RSUs) \| Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded (in shares)		32,000
Time-Based Restricted Stock Units (RSUs) \| Forecast
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense						$ 18.5
Time-Based Restricted Stock Units (RSUs) \| April 28, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent				30.00%
Time-Based Restricted Stock Units (RSUs) \| April 27, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent			30.00%
Time-Based Restricted Stock Units (RSUs) \| May 2, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent				40.00%