Expected Benefit Payments and Subsidy Benefits (Detail) (Other Postretirement Benefit Plans, Defined Benefit, USD $) In Thousands, unless otherwise specified	Dec. 25, 2011
Other Postretirement Benefit Plans, Defined Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2012	$ 20,431
2013	20,035
2014	19,695
2015	18,887
2016	17,848
2017-2021	73,018
2012	2,078
2013	2,057
2014	2,043
2015	2,000
2016	1,953
2017-2021	$ 8,715

The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

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- Definition

The amount of the benefits expected to be paid in Year 5.

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- Definition

The amount of the benefits expected to be paid in Year 4.

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The amount of the benefits expected to be paid in Year 1.

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The amount of the benefits expected to be paid in Year 3.

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The amount of the benefits expected to be paid in Year 2.

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- Definition

Aggregate amount for the next five fiscal years following the first five fiscal years (that is the aggregate of fiscal years six through ten) following the balance sheet date of the prescription drug subsidy receipts expected to be received.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph f

-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 FASB Staff Position (FSP)

-Number FAS106-2

-Paragraph 22

-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 4: 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=6962843&loc=d3e1928-114920

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- Definition

Amount of the prescription drug subsidy receipts expected to be received in Year 5 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 4 after the balance sheet date.

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Amount of the prescription drug subsidy receipts expected to be received in Year 1 after the balance sheet date.

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- Definition

Amount of the prescription drug subsidy receipts expected to be received in Year 3 after the balance sheet date.

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- Definition

Amount of the prescription drug subsidy receipts expected to be received in Year 2 after the balance sheet date.

+ References

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