Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Comparison of basic and diluted earnings per share

The following table sets forth the comparison of basic and diluted earnings per share:

	Year Ended December 31,
	2016		2015		2014
Basic earnings per share:
Net income	$	255.3	$	83.9	$	490.3
Weighted average common shares outstanding	88,275,810		92,530,208		97,538,319
Basic earnings per share	$	2.89	$	0.91	$	5.03

	Year Ended December 31,
	2016		2015		2014
Diluted earnings per share:
Net income	$	255.3	$	83.9	$	490.3
Weighted average common shares outstanding	88,275,810		92,530,208		97,538,319
Share equivalents:
Stock options	839,038		1,031,666		1,432,960
RSU and PU awards	677,033		591,773		605,808
Employee share purchase plan	9,013		20,813		14,686
Weighted average common shares and common share equivalents outstanding — diluted	89,800,894		94,174,460		99,591,773
Diluted earnings per share	$	2.84	$	0.89	$	4.92