Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2019

Share Based Compensation [Abstract]

Summary of Restricted Stock and Performance Unit Award Activity

The following table presents restricted stock and performance unit award activity for the three months ended March 31, 2019:

	Restricted Stock					Performance Units
	Shares			Weighted Average Grant- Date Fair Value		Shares		Weighted Average Grant- Date Fair Value
Outstanding at January 1, 2019		743,591		$	86.90		266,704	$	90.01
Vested		(699	)		80.75		—		—
Forfeitures		(2,720	)		91.44		—		—
Outstanding at March 31, 2019		740,172		$	86.89		266,704	$	90.01

Compensation Expense for Share-Based Awards

Our share-based compensation expense is recorded in "Selling, general, and administrative expenses." Compensation expense for share-based awards recognized in the Consolidated Statements of Income, net of forfeitures, was as follows (dollars in millions):

	Three Months Ended March 31,
	2019			2018
Restricted stock	$	4.9		$	3.9
Performance units		2.0			1.2
Total share-based compensation expense		6.9			5.1
Income tax benefit		(1.7	)		(1.3	)
Share-based compensation expense, net of tax benefit	$	5.2		$	3.8

Unrecognized Compensation Expense for Share-Based Awards

The unrecognized compensation expense for all share-based awards at March 31, 2019 was as follows (dollars in millions):

	March 31, 2019
	Unrecognized Compensation Expense		Remaining Weighted Average Recognition Period (in years)
Restricted stock	$	26.6	2.3
Performance units		12.5		2.4
Total unrecognized share-based compensation expense	$	39.1		2.3