Stock Plans and Share-Based Compensation (Restricted Stock Units) (Details) - Restricted Stock Units (RSUs) [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Dec. 25, 2015	Dec. 26, 2014	Dec. 27, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Long Term Incentive Plan - 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	63	52
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Units Outstanding, beginning balance	1,330	1,318
Granted (in shares)	63	52
Forfeited (in shares)	(76)	(40)
Vested (in shares)	1,317
Unvested, Units Outstanding, beginning balance	0	1,330	1,318
Long Term Incentive Plan - 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	134	1,144
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Units Outstanding, beginning balance	1,119	0
Granted (in shares)	134	1,144
Forfeited (in shares)	(138)	(25)
Vested (in shares)	0
Unvested, Units Outstanding, beginning balance	1,115	1,119	0
Long Term Incentive Plan - 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	935	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Units Outstanding, beginning balance	0	0
Granted (in shares)	935	0
Forfeited (in shares)	(109)	0
Vested (in shares)	0
Unvested, Units Outstanding, beginning balance	826	0	0
Long-term Incentive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected weighted average period of recognition for unrecognized compensation cost (in years)	2 years
Granted (in shares)	312	371	524
Award vesting period	3 years
Unrecognized compensation cost	$ 7
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Granted (in shares)	312	371	524
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Unvested, Weighted-Average Fair Value at Grant Date, beginning balance (dollars per share)	$ 26.66	$ 25.32
Granted, Weighted-Average Fair Value at Grant Date (dollars per share)	35.45	28.11
Forfeited, Weighted-Average Fair Value at Grant Date (dollars per share)	30.06	26.33
Vested, Weighted-Average Fair Value at Grant Date (dollars per share)	25.90
Unvested, Weighted-Average Fair Value at Grant Date, beginning balance (dollars per share)	$ 31.73	$ 26.66	$ 25.32

Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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