CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2013	Mar. 31, 2012
Statement of Other Comprehensive Income [Abstract]
Net earnings	$ 471,253	$ 409,411
Other comprehensive earnings:
Unrealized gain on available-for-sale (AFS) securities, net of tax effect of $21,218 and $13,077 in 2013 and 2012, respectively	33,695	20,766
Reclassification adjustment for net realized gain on AFS securities, net of tax effect of ($1,027) and ($92) in 2013 and 2012, respectively	(1,632)	(146)
Adjustment to postretirement benefit plan obligation, net of tax effect of $508 and $301 in 2013 and 2012, respectively	806	478
Comprehensive earnings	$ 504,122	$ 430,509