Income Taxes - Deferred Taxes (Details) - USD ($) $ in Millions	Dec. 29, 2019	Dec. 30, 2018
Deferred tax assets:
Allowance for doubtful accounts	$ 0.6	$ 0.6
Sundry accruals	2.3	1.1
Vacation accrual	3.0	2.7
Stock-based compensation	5.3	4.2
Payroll related accruals	6.2	2.4
Lease accruals	22.1	2.0
Investments	1.3	1.3
Net operating loss carryforwards	75.1	81.7
Capital loss carryforwards	1.3	1.9
Tax credit carryforwards	11.2	9.9
Deferred revenue	1.1	1.5
Reserves and other	13.6	10.8
Gross deferred tax assets	143.1	120.1
Valuation allowance	(88.6)	(92.2)
Total deferred tax assets, net of valuation allowance	54.5	27.9
Deferred tax liabilities:
Unearned revenue	(19.0)	(23.9)
Deferred Tax Liabilities, Operating Lease Right-of-use Assets	(20.2)
Other intangibles	(21.0)	(8.9)
Property and equipment, principally due to differences in depreciation	(2.0)	(0.9)
Other	(1.3)	(1.2)
Total deferred tax liabilities	(63.5)	(34.9)
Net deferred tax liability	$ (9.0)	$ (7.0)