CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 681	$ 150
Other comprehensive income (loss):
Foreign currency translation adjustments	9	(42)
Changes in unamortized actuarial loss, net of tax expense of $7 and $16	20	44
Changes in unamortized net prior service credit, net of tax benefit of $1 and $0	1	1
Total other comprehensive income	30	3
Total comprehensive income	$ 711	$ 153