Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

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, 2021:

	Restricted Stock					Performance Units
	Shares			Weighted Average Grant- Date Fair Value		Shares		Weighted Average Grant- Date Fair Value
Outstanding at January 1, 2021		669,102		$	102.55		357,417	$	103.63
Granted		168,700			133.54		95,236		140.47
Vested		(3,508	)		102.72		—		—
Forfeitures		(3,284	)		101.05		—		—
Outstanding at March 31, 2021		831,010		$	108.85		452,653	$	111.38

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,
	2021			2020
Restricted stock	$	8.6		$	8.0
Performance units		3.0			2.1
Total share-based compensation expense		11.6			10.1
Income tax benefit		(2.9	)		(2.5	)
Share-based compensation expense, net of tax benefit	$	8.7		$	7.6

Unrecognized Compensation Expense for Share-Based Awards

The unrecognized compensation expense for all share-based awards at March 31, 2021 was as follows (dollars in millions):

	March 31, 2021
	Unrecognized Compensation Expense		Remaining Weighted Average Recognition Period (in years)
Restricted stock	$	39.4		2.9
Performance units		28.0		2.7
Total unrecognized share-based compensation expense	$	67.4		2.8