Selected Quarterly Financial Data (Unaudited) (Details) (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
Selected Quarterly Financial Information [Abstract]
Net sales	$ 757,235		$ 802,577		$ 804,890		$ 768,875		$ 697,804		$ 726,742		$ 701,730		$ 640,583		$ 3,133,577		$ 2,766,859		$ 2,269,471
Gross profit	390,821		414,375		415,151		394,177		357,178		377,381		366,233		333,380		1,614,524		1,434,172		1,174,836
Pre-tax earnings	158,151		175,836		179,039		161,129		140,769		155,319		150,182		128,811		674,155		575,081		430,640
Net earnings	$ 98,716		$ 109,320		$ 112,306		$ 100,194		$ 87,472		$ 96,798		$ 94,112		$ 79,547		$ 420,536		$ 357,929		$ 265,356
Basic net earnings per share	$ 0.33	[1]	$ 0.37	[1]	$ 0.38	[1]	$ 0.34	[1]	$ 0.30	[1]	$ 0.33	[1]	$ 0.32	[1]	$ 0.27	[1]	$ 1.42	[1]	$ 1.21	[1]	$ 0.90

[1] Note – Amounts may not foot due to rounding difference.