Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 25, 2018
Operating activities
Net earnings	$ 1,704	$ 1,157
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation and amortization	277	279
Stock-based compensation	37	38
Gain on property sale	(51)	0
Changes in assets and liabilities
Receivables, net	(389)	(108)
Contract assets	(1,025)	(1,413)
Inventories	(288)	(318)
Accounts payable	744	1,290
Contract liabilities	305	(478)
Postretirement benefit plans	278	(1,145)
Income taxes	243	1,064
Other, net	(172)	266
Net cash provided by operating activities	1,663	632
Investing activities
Capital expenditures	(284)	(216)
Other, net	27	130
Net cash used for investing activities	(257)	(86)
Financing activities
Dividends paid	(638)	(586)
Repurchases of common stock	(281)	(300)
Repayments of commercial paper, net	(200)	0
Other, net	(68)	(128)
Net cash used for financing activities	(1,187)	(1,014)
Net change in cash and cash equivalents	219	(468)
Cash and cash equivalents at beginning of period	772	2,861
Cash and cash equivalents at end of period	$ 991	$ 2,393

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