Income Taxes - Summary of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred income tax assets:
Federal net operating loss carryforward	$ 67.9	$ 54.5
State net operating loss carryforward	11.7	14.2
Total deferred tax assets	79.6	68.7
Deferred tax liabilities:
Property, equipment, and intangible assets	(440.6)	(414.9)
Other	(1.4)	0.0
Total deferred tax liabilities	(442.0)	(414.9)
Deferred tax liability, net	$ (362.4)	$ (346.2)