Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 3,747	$ 2,790	$ 1,935
Other comprehensive income (loss)
Debt securities	36	(13)	(1)
Currency translation adjustments	4	(8)	3
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	(23)	23	(13)
Other comprehensive income (loss)	17	2	(11)
Comprehensive income	$ 3,764	$ 2,792	$ 1,924