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Amount of loss contingency liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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Casualty, Environmental and Other Reserves (Loss Contingencies Accrual) (Details) (USD $) In Millions, unless otherwise specified	Dec. 26, 2014	Dec. 27, 2013	Dec. 28, 2012	Dec. 30, 2011
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	$ 142	$ 151
Loss Contingency, Accrual, Noncurrent	276	300
Casualty [Member]
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	76	72
Loss Contingency, Accrual, Noncurrent	189	208
Loss Contingency Accrual	265	280	325	372
Personal Injury [Member]
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	68	59
Loss Contingency, Accrual, Noncurrent	123	148
Loss Contingency Accrual	191	207
Occupational [Member]
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	3	3
Loss Contingency, Accrual, Noncurrent	15	20
Loss Contingency Accrual	18	23
Asbestos [Member]
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	5	10
Loss Contingency, Accrual, Noncurrent	51	40
Loss Contingency Accrual	56	50
Environmental [Member]
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	48	59
Loss Contingency, Accrual, Noncurrent	46	41
Loss Contingency Accrual	94	100	88	83
Other Reserves [Member]
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	18	20
Loss Contingency, Accrual, Noncurrent	41	51
Loss Contingency Accrual	59	71	64	64
Casualty, Environmental and Other [Member]
Contingencies [Line Items]
Casualty, Environmental and Other Reserves	142	151
Loss Contingency, Accrual, Noncurrent	276	300
Loss Contingency Accrual	$ 418	$ 451	$ 477	$ 519