Tax year being audited in the income tax examination, in CCYY format.

No definition available.

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Period Type:	duration

- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

+ Details

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

- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32559-109319

+ Details

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

- Definition

Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

Name:	us-gaap_TaxPeriodAxis=us-gaap_LatestTaxYearMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=wmk_PennsylvaniaMember
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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Operating Loss Carryforwards	$ 86.2
Earliest Tax Year [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2027
Latest Tax Year [Member]
Internal Revenue Service income tax examination, year	2008
Federal [Member]
Income Taxes Paid	$ 27.3	$ 28.0	$ 25.0
State [Member]
Income Taxes Paid	$ 3.7	$ 2.2	$ 1.8
Pennsylvania [Member] \| Earliest Tax Year [Member]
Open Tax Year	2012
Pennsylvania [Member] \| Latest Tax Year [Member]
Open Tax Year	2016