Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 25, 2018	Mar. 26, 2017
Operating activities
Net earnings	$ 1,157	$ 789
Adjustments to reconcile net earnings to net cash provided by operating activities
Depreciation and amortization	279	285
Stock-based compensation	38	44
Changes in assets and liabilities
Receivables, net	(108)	(799)
Contract assets	(1,413)	(62)
Inventories	(318)	(225)
Accounts payable	1,290	1,111
Contract liabilities	(478)	(185)
Postretirement benefit plans	(1,145)	345
Income taxes	1,064	175
Other, net	266	188
Net cash provided by operating activities	632	1,666
Investing activities
Capital expenditures	(216)	(170)
Other, net	130	4
Net cash used for investing activities	(86)	(166)
Financing activities
Repurchases of common stock	(300)	(500)
Dividends paid	(586)	(544)
Proceeds from stock option exercises	33	31
Other, net	(161)	(108)
Net cash used for financing activities	(1,014)	(1,121)
Net change in cash and cash equivalents	(468)	379
Cash and cash equivalents at beginning of period	2,861	1,837
Cash and cash equivalents at end of period	$ 2,393	$ 2,216