Acquisitions (Tables)

6 Months Ended

Jun. 30, 2011

Acquisitions [Abstract]

Summary of pro-forma consolidated financial information

(Thousands of dollars except per share data)
	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2011		2010		2011		2010
Net sales	$	2,354,751	$	2,237,528	$	4,211,127	$	3,932,805
Net income		179,115		185,761		247,562		220,653
Net income per common share:
Basic	$	1.69	$	1.71	$	2.34	$	2.03
Diluted	$	1.66	$	1.67	$	2.29	$	2.00