Income Taxes (Unrecognized Tax Benefits) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 26, 2014	Dec. 27, 2013	Dec. 28, 2012
Income Tax Disclosure [Abstract]
Amount of unrecognized tax benefits that may favorably effect the effective income tax rate	$ 13	$ 15	$ 17
Amount of unrecognized tax benefits that will be resolved over next twelve months	2
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of the year	23us-gaap_UnrecognizedTaxBenefits	24us-gaap_UnrecognizedTaxBenefits	22us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to current year	2	2	6
Additions based on tax positions related to prior years	3	5	3
Reductions based on tax positions related to prior years	0	(6)	(1)
Settlements with taxing authorities	0	0	0
Lapse of statute of limitations	(7)	(2)	(6)
Balance at end of the year	$ 21us-gaap_UnrecognizedTaxBenefits	$ 23us-gaap_UnrecognizedTaxBenefits	$ 24us-gaap_UnrecognizedTaxBenefits

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- Definition

The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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