Income Taxes - Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current
Federal	$ 31.2	$ 1.3	$ (17.4)
State	3.8	0.7	1.8
Current Income Tax Expense (Benefit)	34.9	2.0	(15.6)
Deferred
Federal	(7.6)	(8.8)	32.5
State	(0.3)	(0.9)	4.2
Deferred tax expense	(7.9)	(9.7)	36.7
Income tax provision	27.0	(7.7)	21.1
Income Tax Examination [Line Items]
Federal	31.2	1.3	(17.4)
State	3.8	0.7	1.8
Current Income Tax Expense (Benefit)	34.9	2.0	(15.6)
Federal	(7.6)	(8.8)	32.5
State	(0.3)	(0.9)	4.2
Deferred taxes	(7.9)	(9.7)	36.7
Income tax (provision) benefit	27.0	$ (7.7)	$ 21.1
Valuation allowances, State Tax Credits [Member]
Income Tax Examination [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 2.7