Income Taxes - Deferred Taxes (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 25, 2022
Deferred tax assets:
Stock-based compensation	$ 9.3	$ 9.4
Payroll related accruals	8.6	6.7
Lease accruals	27.0	25.7
Net operating loss carryforwards	44.7	55.1
Tax credit carryforwards	12.2	11.3
Deferred expenses	12.6	14.1
Other	19.8	19.4
Gross deferred tax assets	134.2	141.7
Valuation allowance	(12.6)	(14.6)
Total deferred tax assets, net of valuation allowance	121.6	127.1
Deferred tax liabilities:
Unearned revenue	(2.9)	(3.3)
Operating lease right-of-use assets	(24.2)	(23.2)
Other intangibles	(22.2)	(23.1)
Property and equipment, principally due to differences in depreciation	(6.3)	(5.6)
Other	(2.0)	(1.6)
Total deferred tax liabilities	(57.6)	(56.8)
Net deferred tax asset	$ 64.0	$ 70.3