Leases (Narrative) (Details) - USD ($) $ in Millions	Sep. 27, 2020	Jul. 31, 2020	Apr. 30, 2020
Property Subject to or Available for Operating Lease [Line Items]
Lease term (in years)	20 years
Amount of rent deferred under temporary rent concessions		$ 15.5
Lease liabilities subject to accretion	$ 947.8
Lease liability related to rent deferrals	7.2
Portion of April rents due from franchisees that has been postponed (percent)			40.00%
Portion of April rents due from franchisees that has been postponed			$ 9.1
Rent concessions secured for landlords passed on to franchisees		$ 5.6
Uncollected rent concessions	$ 2.6
Minimum
Property Subject to or Available for Operating Lease [Line Items]
Lease renewal option as lessor (in years)	1 year
Minimum | Restaurant and Office Equipment
Property Subject to or Available for Operating Lease [Line Items]
Lease term (in years)	3 years
Maximum
Property Subject to or Available for Operating Lease [Line Items]
Lease renewal option as lessor (in years)	20 years
Maximum | Restaurant and Office Equipment
Property Subject to or Available for Operating Lease [Line Items]
Lease term (in years)	8 years