Unaudited Interim Financial Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2012	Dec. 31, 2011		Dec. 31, 2010
Quarterly Financial Data [Line Items]
Net sales	$ 762,600	$ 722,900	$ 742,600	$ 730,000	$ 751,900		$ 719,200		$ 725,000		$ 700,300		$ 2,958,100	$ 2,896,400		$ 2,720,200
Cost of goods sold	287,600	272,600	285,700	279,400	282,100		274,900		275,500		264,800		1,125,300	1,097,300		1,020,000
Income from operations before income taxes	177,300	178,200	185,500	191,400	142,000		182,100		2,700		184,000		732,400	510,800		717,700
Net income (loss) attributable to common shareholders	$ 128,200	$ 129,300	$ 133,900	$ 138,700	$ 113,800		$ 130,100		$ (47,800)		$ 131,900		$ 530,100	$ 328,000		$ 509,200
Basic earnings (loss) per share available to common shareholders	$ 1.54	$ 1.52	$ 1.56	$ 1.62	$ 1.31	[1]	$ 1.48	[1]	$ (0.55)	[1]	$ 1.52	[1]	$ 6.24	$ 3.75	[1]	$ 5.39
Diluted earnings (loss) per share available to common shareholders	$ 1.52	$ 1.50	$ 1.54	$ 1.60	$ 1.30	[1]	$ 1.46	[1]	$ (0.55)	[1],[2]	$ 1.49	[1]	$ 6.16	$ 3.69	[1]	$ 5.32

[1] Total per share amounts may not add due to rounding.

[2] Common share equivalents primarily from share-based compensation plans were not included in the computation of diluted weighted average shares outstanding because their effect would have been antidilutive.