Earnings Per Share Earnings Per Share (Details) - $ / shares shares in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Document Period End Date	Mar. 31, 2019
Basic and diluted weighted average shares outstanding (a)	75.8	81.0
Basic	$ (1.20)	$ (1.08)
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		0.1
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1.3	1.5