Earnings Per Share - Computation of Basic and Diluted Net EPS (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share [Abstract]
Net earnings	$ 60.0	$ 74.6	$ 93.5	$ 40.5	$ 33.5	$ 61.7	$ 71.7	$ 28.1	$ 268.6	$ 195.0	$ 144.1
Weighted average number of common shares outstanding									128.9	121.0	111.7
Dilutive effect of stock options using the treasury stock method									1.6	1.5	0.8
Weighted average number of common and common equivalent shares outstanding									130.5	122.5	112.5
Basic net earnings per share									$ 2.08	$ 1.61	$ 1.29
Diluted net earnings per share:									$ 2.06	$ 1.59	$ 1.28