Revenue Recognition - Transition Disclosures, Statement of Earnings (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Transition Disclosures
Revenue	$ 19,072	$ 18,155
Cost	10,825	10,211	[1]
Gross profit	8,247	7,944	[1]
Selling, general and administrative	5,445	5,027	[1]
Income from continuing operations before income taxes	1,136	1,424
Provision for/(benefit from) income taxes	(540)	(329)
Net income	$ 1,679	$ 1,750
Earnings/(loss) per share of common stock:
Assuming dilution (in dollars per share)	$ 1.81	$ 1.85
Basic (in dollars per share)	$ 1.82	$ 1.86
Accounting Standards Update 2014-09, Revenue from Contracts with Customers | Adjustments to convert to prior GAAP
Transition Disclosures
Revenue	$ (52)
Cost	(25)
Gross profit	(28)
Selling, general and administrative	(21)
Income from continuing operations before income taxes	(7)
Provision for/(benefit from) income taxes	(2)
Net income	$ (5)
Earnings/(loss) per share of common stock:
Assuming dilution (in dollars per share)	$ 0.00
Basic (in dollars per share)	$ (0.01)
Accounting Standards Update 2014-09, Revenue from Contracts with Customers | Adjusted amounts under prior GAAP
Transition Disclosures
Revenue	$ 19,020
Cost	10,800
Gross profit	8,220
Selling, general and administrative	5,424
Income from continuing operations before income taxes	1,129
Provision for/(benefit from) income taxes	(542)
Net income	$ 1,674
Earnings/(loss) per share of common stock:
Assuming dilution (in dollars per share)	$ 1.81
Basic (in dollars per share)	$ 1.81

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