Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share-based Compensation, Stock Options, Activity [Table Text Block]

	Quarter Ended					Nine Months Ended
	September 30,					September 30,
Dollar amounts in millions	2018			2017		2018			2017
Total stock-based compensation expense (cost of sales, selling, general and administrative and other operating credits and charges, net)	$	2.1		$	2.0	$	6.9		$	8.0
Income tax provision related to stock-based compensation	(0.3		)	0.2		(3.1		)	0.5
Impact on cash flow due to taxes paid related to net share settlement of equity awards	1.5			0.5		9.3			5.3