Supplemental Equity and Comprehensive Income Information - SE Rf (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Increase (decrease) in equity
Balance at the beginning of the period	$ 10,126	$ 9,848
Net income	1,294	893
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	(444)	77
Defined benefit pension and postretirement plans adjustment	119	84
Cash flow hedging instruments	47	6
Total other comprehensive income (loss), net of tax	(278)	167
Dividends declared	(847)	(830)
Stock-based compensation	117	112
Reacquired stock	(356)	(666)
Issuances pursuant to stock option and benefit plans	153	219
Balance at the end of the period	10,209	9,757
ASU 2016-02 Leases
Increase (decrease) in equity
Impact of ASUs		14
Common Stock and Additional Paid-in Capital
Increase (decrease) in equity
Balance at the beginning of the period	5,916	5,652
Other comprehensive income (loss), net of tax:
Stock-based compensation	117	112
Balance at the end of the period	6,033	5,764
Retained Earnings
Increase (decrease) in equity
Balance at the beginning of the period	42,135	40,636
Net income	1,292	891
Other comprehensive income (loss), net of tax:
Dividends declared	(847)	(830)
Issuances pursuant to stock option and benefit plans	(235)	(405)
Balance at the end of the period	42,345	41,159
Retained Earnings | ASU 2018-02 Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income
Increase (decrease) in equity
Impact of ASUs		853
Retained Earnings | ASU 2016-02 Leases
Increase (decrease) in equity
Impact of ASUs		14
Treasury Stock
Increase (decrease) in equity
Balance at the beginning of the period	(29,849)	(29,626)
Other comprehensive income (loss), net of tax:
Reacquired stock	(356)	(666)
Issuances pursuant to stock option and benefit plans	388	624
Balance at the end of the period	(29,817)	(29,668)
Total Accumulated Other Comprehensive Income (Loss)
Increase (decrease) in equity
Balance at the beginning of the period	(8,139)	(6,866)
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	(441)	77
Defined benefit pension and postretirement plans adjustment	119	84
Cash flow hedging instruments	47	6
Balance at the end of the period	(8,414)	(7,552)
Total Accumulated Other Comprehensive Income (Loss) | ASU 2018-02 Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income
Increase (decrease) in equity
Impact of ASUs		(853)
Noncontrolling Interest
Increase (decrease) in equity
Balance at the beginning of the period	63	52
Net income	2	2
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	(3)
Balance at the end of the period	$ 62	$ 54