Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jul. 01, 2012	Jun. 30, 2013	Jul. 01, 2012
Earnings Per Share (Thousands of Dollars and Shares Except Per Share Data) [Abstract]
Net earnings	$ 36,480	$ 43,427	$ 29,809	$ 40,848
Basic [Abstract]
Average Shares Outstanding	130,323	130,294	129,831	129,918
Equivalent shares (basic) (in shares)	130,323	130,294	129,831	129,918
Net earnings per common share-basic (in dollars per share)	$ 0.28	$ 0.33	$ 0.23	$ 0.31
Diluted [Abstract]
Average Shares Outstanding	130,323	130,294	129,831	129,918
Effect of dilutive securities:
Options and other share-based awards (in shares)	1,657	1,824	1,606	1,907
Equivalent shares (diluted) (in shares)	131,980	132,118	131,437	131,825
Net earnings per common share-diluted (in dollars per share)	$ 0.28	$ 0.33	$ 0.23	$ 0.31
Options to acquire shares totaling excluded as antidilutive	1,849	3,504	1,511	3,523