Basis of Presentation (Unaudited) Contract Estimates (Details 2) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Change in Accounting Estimate [Line Items]
Revenue	$ 116	$ 124	$ 478	$ 385
Operating income	1,043	985	4,909	2,913
Net earnings	$ 1,063	$ 986	$ 4,295	$ 2,859
Diluted earnings per share	$ 6.63	$ 5.89	$ 26.55	$ 17.05
Contracts Accounted for under Percentage of Completion [Member]
Change in Accounting Estimate [Line Items]
Operating income	$ 109	$ 123	$ 453	$ 359
Net earnings	$ 86	$ 97	$ 358	$ 284
Diluted earnings per share	$ 0.54	$ 0.58	$ 2.21	$ 1.69