Summary of Significant Accounting Policies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 26, 2012	Dec. 28, 2011	Dec. 29, 2010
Accounting Policies [Abstract]
Short-term investments	$ 11.8	$ 12.0
Net gain/(loss) on investments (less than $0.1 million in 2011)	0.7	(0.1)	0.5
Deferred compensation plan investments	6.4	4.9
Cash overdrafts	6.3	7.8
Maximum self-insurance retention levels, minimum per individual claim	0.5
Maximum self-insurance retention levels, maximum per individual claim	1.0
Discounted insurance liabilities	23.2	24.6
Self insurance liabilities, discount rate	1.00%	1.50%
Undiscounted insurance liabilities	23.8	25.6
Revenue recognized in breakage on gift cards	0.3	0.3
Initial franchise fees	3.0	3.1	6.6
Deferred fees	1.2	1.1
Concentration Risk [Line Items]
Advertising expense	13.4	16.1	17.4
Advertising contributions from franchisees	$ 65.1	$ 60.5	$ 52.1
Franchise and license fees \| Revenue from franchises and licenses risk
Concentration Risk [Line Items]
Franchise revenue, percentage	32.00%	34.00%	33.00%

Total amount of contributions received from an entity's franchisees to be used for advertising expenses

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Maximum Self-Insurance Retention Levels, Per Individual Claim, Maximum

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Maximum Self-Insurance Retention Levels, Per Individual Claim, Minimum

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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The amount of initial franchise fees.

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The rate applied as of the balance sheet date to reduce the undiscounted amount of a guarantee fund and other insurance-related assessments to present value.

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The present value of the liability as of the balance sheet date representing required funding mandated by statute or regulatory authority that is related directly or indirectly to underwriting activities, including pools for self-insurance and excluding premium taxes and income taxes. The funds derived from the assessments generally enable a government guarantor to pay insurance claims in the event that the underwriting insurer is insolvent or otherwise unable to meet its payment obligations.

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The liability as of the balance sheet date representing required funding mandated by statute or regulatory authority that is related directly or indirectly to underwriting activities, including pools for self-insurance and excluding premium taxes and income taxes. The funds derived from the assessments generally enable a government guarantor to pay insurance claims in the event that the underwriting insurer is insolvent or otherwise unable to meet its payment obligations.

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The amount of breakage recognized related to unredeemed gift cards. Breakage occurs when a customer pays in advance of vendor performance and does not demand full performance for various reasons.

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Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

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