Supplemental Equity and Comprehensive Income Information - SE Rf (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Increase (decrease) in equity
Balance at the beginning of the period	$ 11,937	$ 13,130	$ 11,747	$ 13,142
Net income	1,331	1,298	3,902	3,802
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	17	(472)	192	(642)
Defined benefit pension and postretirement plans adjustment	67	236	203	423
Cash flow hedging instruments - unrealized gain (loss)	(45)	1	(182)	39
Total other comprehensive income (loss), net of tax	39	(235)	213	(180)
Dividends declared	(670)	(635)	(2,014)	(1,284)
Stock-based compensation, net of tax impacts in 2015	49	46	221	352
Reacquired stock	(771)	(1,449)	(2,771)	(4,132)
Issuances pursuant to stock option and benefit plans	133	69	750	524
Balance at the end of the period	12,048	12,224	12,048	12,224
Common Stock and Additional Paid-in Capital
Increase (decrease) in equity
Balance at the beginning of the period	4,972	4,694	4,800	4,388
Other comprehensive income (loss), net of tax:
Stock-based compensation, net of tax impacts in 2015	49	46	221	352
Balance at the end of the period	5,021	4,740	5,021	4,740
Retained Earnings
Increase (decrease) in equity
Balance at the beginning of the period	37,194	35,615	36,575	34,317
Net income	1,329	1,296	3,895	3,795
Other comprehensive income (loss), net of tax:
Dividends declared	(670)	(635)	(2,014)	(1,284)
Issuances pursuant to stock option and benefit plans	(108)	(41)	(711)	(593)
Balance at the end of the period	37,745	36,235	37,745	36,235
Treasury Stock
Increase (decrease) in equity
Balance at the beginning of the period	(24,088)	(20,983)	(23,308)	(19,307)
Other comprehensive income (loss), net of tax:
Reacquired stock	(771)	(1,449)	(2,771)	(4,132)
Issuances pursuant to stock option and benefit plans	241	110	1,461	1,117
Balance at the end of the period	(24,618)	(22,322)	(24,618)	(22,322)
Accumulated Other Comprehensive Income (Loss)
Increase (decrease) in equity
Balance at the beginning of the period	(6,184)	(6,233)	(6,359)	(6,289)
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	16	(471)	192	(640)
Defined benefit pension and postretirement plans adjustment	67	236	203	423
Cash flow hedging instruments - unrealized gain (loss)	(45)	1	(182)	39
Balance at the end of the period	(6,146)	(6,467)	(6,146)	(6,467)
Noncontrolling Interest
Increase (decrease) in equity
Balance at the beginning of the period	43	37	39	33
Net income	2	2	7	7
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	1	(1)		(2)
Balance at the end of the period	$ 46	$ 38	$ 46	$ 38