CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 917,584	$ 574,026	$ 2,951,974	$ 2,216,054
Other Comprehensive Earnings [Abstract]
Unrealized gain on debt securities net of income taxes in 2020 and 2019, respectively.	5,456	22,131	127,951	139,782
Reclassification adjustment for net realized gain on debt securities net of income taxes in 2020 and 2019, respectively.	(3,678)	(439)	(7,599)	(109)
Adjustment to postretirement benefit obligation net of income taxes in 2020.	814	0	2,443	0
Comprehensive earnings	$ 920,176	$ 595,718	$ 3,074,769	$ 2,355,727