Revenue Recognition - Transition Disclosures, Statement of Earnings (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Transition Disclosures
Revenue	$ 18,756	$ 19,153		$ 57,830	$ 56,597
Cost	9,953	10,172	[1]	31,582	30,703	[1]
Gross profit	8,803	8,981	[1]	26,249	25,894	[1]
Selling, general and administrative	4,363	4,606	[1]	14,665	14,666	[1]
Income from continuing operations before income taxes	2,996	3,065		6,908	6,931
Provision for (benefit from) income taxes	304	339		138	120
Net income	$ 2,694	$ 2,726		$ 6,777	$ 6,807
Earnings/(loss) per share of common stock:
Assuming dilution (in dollars per share)	$ 2.94	$ 2.92		$ 7.36	$ 7.24
Basic (in dollars per share)	$ 2.95	$ 2.93		$ 7.39	$ 7.28
Accounting Standards Update 2014-09, Revenue from Contracts with Customers | Adjustments to convert to prior GAAP
Transition Disclosures
Revenue	$ 4			$ (10)
Cost				0
Gross profit	4			(10)
Selling, general and administrative	(28)			(32)
Income from continuing operations before income taxes	33			23
Provision for (benefit from) income taxes	8			5
Net income	$ 24			$ 17
Earnings/(loss) per share of common stock:
Assuming dilution (in dollars per share)	$ 0.03			$ 0.02
Basic (in dollars per share)	$ 0.03			$ 0.02
Accounting Standards Update 2014-09, Revenue from Contracts with Customers | Adjusted amounts under prior GAAP
Transition Disclosures
Revenue	$ 18,760			$ 57,821
Cost	9,953			31,582
Gross profit	8,807			26,239
Selling, general and administrative	4,335			14,633
Income from continuing operations before income taxes	3,029			6,930
Provision for (benefit from) income taxes	313			143
Net income	$ 2,718			$ 6,794
Earnings/(loss) per share of common stock:
Assuming dilution (in dollars per share)	$ 2.97			$ 7.38
Basic (in dollars per share)	$ 2.98			$ 7.41

[1] Recast to reflect adoption of the FASB guidance on presentation of net periodic pension and nonpension postretirement benefit costs.