Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Computation of Basic and Diluted Earnings per Share

	Three Months Ended
	March 31,
(in millions, except per share data)	2021		2020
Net income attributable to common shareholders	$	108.4	$	62.8
Average basic shares outstanding	58.2		58.8
Effect of dilutive share-based awards	0.7		0.8
Average diluted shares outstanding	58.9		59.6
Earnings per basic share	$	1.86	$	1.07
Earnings per diluted share	$	1.84	$	1.05