Share-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

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 six months ended June 30, 2017:

	Restricted Stock					Performance Units
	Shares			Weighted Average Grant- Date Fair Value		Shares			Weighted Average Grant- Date Fair Value
Outstanding at January 1, 2017		786,079		$	63.44		232,088		$	62.68
Granted		173,199			107.57		61,861			108.19
Vested		(206,707	)		51.05		(67,391	)		56.08
Forfeitures		(4,341	)		65.51		—			—
Outstanding at June 30, 2017		748,230		$	77.07		226,558		$	77.07

Compensation Expense for Restricted Stock and Performance Units

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 June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
Restricted stock	$	4.1		$	3.9		$	7.5		$	8.8
Performance units		1.5			0.8			2.7			1.5
Total share-based compensation expense		5.6			4.7			10.2			10.3
Income tax benefit		(2.1	)		(1.8	)		(3.9	)		(4.0	)
Share-based compensation expense, net of tax benefit	$	3.5		$	2.9		$	6.3		$	6.3

Unrecognized Compensation For Restricted Stock and Performance Units

The unrecognized compensation expense for all share-based awards at June 30, 2017 was as follows (dollars in millions):

	June 30, 2017
	Unrecognized Compensation Expense		Remaining Weighted Average Recognition Period (in years)
Restricted stock	$	38.2	2.9
Performance units		12.0	3.2
Total unrecognized share-based compensation expense	$	50.2		3.0