Income Taxes - Deferred Income Taxes, Net (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets
Allowances and other reserves	$ 3.1	$ 2.2
Net operating loss carryforwards	76.7	82.1
Capitalized research expenses	24.7
Other		0.9
Total deferred tax assets	104.5	85.2
Less: valuation allowance	(26.6)	(35.5)	$ (30.8)
Deferred tax asset	77.9	49.7
Deferred tax liabilities
Depreciation and amortization	(149.1)	(145.8)
Franchise operating rights	(151.8)	(161.5)
Other	(2.3)
Total deferred tax liabilities	(303.2)	(307.3)
Net deferred tax liabilities	$ (225.3)	$ (257.6)