Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Valuation Allowance [Line Items]
Gross deferred federal, state and local tax benefit	$ 6.5
Deferred federal, state and local tax benefit	8.2
Deferred tax assets, tax deferred expense, employee compensation	(1.7)
Change in valuation allowance	6.6
Valuation allowance	356.8		$ 336.4
Federal and State
Valuation Allowance [Line Items]
Deferred federal, state and local tax benefit	9.5
Change in valuation allowance	8.3	$ 24.6
ASC 842
Valuation Allowance [Line Items]
Change in valuation allowance	$ 13.8