Income Taxes - Schedule of Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Deferred compensation plans	$ 5.8	$ 6.5
Deferred income	5.6	4.7
Allowance for uncollectible receivables	0.9	0.8
Deferred liabilities	2.2	2.1
Net operating losses and credit carryforward	3.7	5.1
Deferred tax assets	18.2	19.2
Valuation allowance	(0.2)	(0.2)
Net deferred tax asset	18.0	19.0
Deferred tax liabilities:
Intangible assets in excess of tax basis	49.3	29.2
Property and equipment in excess of tax basis	38.7	22.4
Equity investments in excess of tax basis	6.9	6.8
Other	1.3	1.2
Deferred tax liabilities	96.2	59.6
Net deferred tax liability	$ (78.2)	$ (40.6)