Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2016

Earnings Per Share [Abstract]

Computation of Basic and Diluted Earnings per Share

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
(in millions, except per share data)	2016		2015		2016		2015
Net income attributable to common shareholders	$	63.5	$	56.9	$	186.8	$	163.7
Average basic shares outstanding	58.5		58.1		58.3		58.0
Effect of dilutive stock options	0.9		0.7		0.9		0.8
Average diluted shares outstanding	59.4		58.8		59.2		58.8
Earnings per basic share	$	1.09	$	0.98	$	3.20	$	2.82
Earnings per diluted share	$	1.07	$	0.97	$	3.16	$	2.78