Debt And Financing - Cash and Cash Equivalents and Managed Accessibility (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Cash and cash equivalents	$ 227,600,000	$ 91,600,000
2014 ABL Facility Credit Agreement [Member]
Debt Instrument [Line Items]
Cash and cash equivalents	227,600,000.0	91,600,000.0
Less: amounts placed into restricted cash subsequent to year-end	(25,000,000)	0
Managed Accessibility	1,200,000	26,700,000
Cash, cash equivalents and managed accessibility	$ 203,800,000	$ 118,300,000