Percentage of grants with performance-based (Operating ratio) vesting provisions.

No definition available.

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- Definition

Percentage of grants with performance-based (Return on Assets) vesting provisions.

+ References

No definition available.

+ Details

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- Definition

This element represents the number of current and/or former employees that have stock options outstanding as of the end of the period.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ 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 (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ 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)(1)(iv)(4)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of options outstanding, including both vested and non-vested options.

+ 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Period Type:	instant

- Details

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option 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)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Details

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

+ References

No definition available.

+ Details

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

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

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Stock Plans and Share-Based Compensation (Stock Options) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended						0 Months Ended
	Dec. 27, 2013	Dec. 28, 2012	Dec. 30, 2011	Dec. 27, 2013 Employee Stock Option [Member] employees	Dec. 28, 2012 Employee Stock Option [Member]	Dec. 30, 2011 Employee Stock Option [Member]	May 07, 2013 Two Thousand Thirteen Long-Term Incentive Plan (2013 LTIP) [Member] Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage Of Grants With Performance Vesting, Operating Ratio							50.00%
Share Based Compensation Arrangement By Share Based Payment Award Number Of Current Or Former Employees With Outstanding Stock Optons				0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value				$ 27	$ 37	$ 84
Percentage Of Grants With Performance Vesting, Return On Assets							50.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding & Exercisable at Beginning of Year (in shares)	1,672	4,145	9,111
Expired or Cancelled (in shares)	(9)	(15)	(27)
Exercised (in shares)	(1,663)	(2,458)	(4,939)
Outstanding & Exercisable at End of Year (in shares)	0	1,672	4,145
Weighted-Average Exercise Price [Abstract]
Outstanding & Exercisable (in dollars per share)	$ 5.36	$ 5.64	$ 5.82
Expired or cancelled (in dollars per share)	$ 5.36	$ 6.36	$ 6.44
Exercised (in dollars per share)	$ 5.36	$ 5.83	$ 5.96
Outstanding & Exercisable (in dollars per share)	$ 0.00	$ 5.36	$ 5.64