Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities
Net earnings	$ 6,230	$ 5,046	$ 1,963
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation and amortization	1,189	1,161	1,195
Stock-based compensation	189	173	158
Deferred income taxes	222	(244)	3,448
Severance and restructuring charges	0	96	0
Gain on property sale	(51)	0	(198)
Gain on divestiture of IS&GS business	0	0	(73)
Changes in assets and liabilities
Receivables, net	107	(179)	(902)
Contract assets	378	(1,480)	390
Inventories	(622)	(119)	(79)
Accounts payable	(1,098)	914	(189)
Contract liabilities	563	(537)	353
Postretirement benefit plans	81	(3,574)	1,316
Income taxes	(151)	1,077	(1,210)
Other, net	274	804	304
Net cash provided by operating activities	7,311	3,138	6,476
Investing activities
Capital expenditures	(1,484)	(1,278)	(1,177)
Other, net	243	203	30
Net cash used for investing activities	(1,241)	(1,075)	(1,147)
Financing activities
Repurchases of common stock	(1,200)	(1,492)	(2,001)
Dividends paid	(2,556)	(2,347)	(2,163)
Proceeds from issuance of commercial paper, net	(600)	600	0
Repayments of long-term debt	(900)	(750)	0
Other, net	(72)	(163)	(141)
Net cash used for financing activities	(5,328)	(4,152)	(4,305)
Net change in cash and cash equivalents	742	(2,089)	1,024
Cash and cash equivalents at beginning of year	772	2,861	1,837
Cash and cash equivalents at end of year	$ 1,514	$ 772	$ 2,861