Inventories (Merchandise Inventories) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Inventories [Abstract]
LIFO Inventory Amount	$ 193,621us-gaap_LIFOInventoryAmount	$ 187,178us-gaap_LIFOInventoryAmount
Weighted Average Cost Inventory Amount	46,020	53,274
Inventories	239,641wmk_Inventories	240,452wmk_Inventories
Excess of Replacement or Current Costs over Stated LIFO Value	$ 79,933	$ 79,022

The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(c))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph c

-Article 5

+ Details

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- Details

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- Definition

The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766

+ Details

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- Definition

The amount of weighted average cost inventory present at the reporting date when inventory is valued using different valuation methods.

+ References

+ Details

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- Definition

Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer). This also reflects the difference between (a) inventory at the lower of LIFO cost or market and (b) inventory at replacement cost or at the lower of some acceptable inventory accounting method (such as FIFO or average cost), or market. If material, reflects an excess of replacement or current cost over stated LIFO value parenthetically on the balance sheet or in a note to the financial statements.

+ References

No definition available.

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