Supplemental Equity and Comprehensive Income Information - SE Rf (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Increase (decrease) in equity
Balance at the beginning of the period	$ 13,130	$ 17,846	$ 13,142	$ 17,948
Net income	1,298	1,311	3,802	3,819
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	(472)	(603)	(642)	(456)
Defined benefit pension and postretirement plans adjustment	236	59	423	180
Debt and equity securities - unrealized gain (loss)		(1)		1
Cash flow hedging instruments - unrealized gain (loss)	1	68	39	61
Total other comprehensive income (loss), net of tax	(235)	(477)	(180)	(214)
Dividends declared	(635)	(550)	(1,284)	(1,105)
Purchase of subsidiary shares		(865)		(870)
Stock-based compensation, net of tax impacts	46	69	352	336
Reacquired stock	(1,449)	(1,283)	(4,132)	(4,438)
Issuances pursuant to stock option and benefit plans	69	155	524	730
Balance at the end of the period	12,224	16,206	12,224	16,206
Common Stock and Additional Paid-in Capital
Increase (decrease) in equity
Balance at the beginning of the period	4,694	4,650	4,388	4,384
Other comprehensive income (loss), net of tax:
Purchase of subsidiary shares		(433)		(434)
Stock-based compensation, net of tax impacts	46	69	352	336
Balance at the end of the period	4,740	4,286	4,740	4,286
Retained Earnings
Increase (decrease) in equity
Balance at the beginning of the period	35,615	33,836	34,317	32,416
Net income	1,296	1,303	3,795	3,777
Other comprehensive income (loss), net of tax:
Dividends declared	(635)	(550)	(1,284)	(1,105)
Issuances pursuant to stock option and benefit plans	(41)	(105)	(593)	(604)
Balance at the end of the period	36,235	34,484	36,235	34,484
Treasury Stock
Increase (decrease) in equity
Balance at the beginning of the period	(20,983)	(17,466)	(19,307)	(15,385)
Other comprehensive income (loss), net of tax:
Reacquired stock	(1,449)	(1,283)	(4,132)	(4,438)
Issuances pursuant to stock option and benefit plans	110	260	1,117	1,334
Balance at the end of the period	(22,322)	(18,489)	(22,322)	(18,489)
Accumulated Other Comprehensive Income (Loss)
Increase (decrease) in equity
Balance at the beginning of the period	(6,233)	(3,666)	(6,289)	(3,913)
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	(471)	(593)	(640)	(462)
Defined benefit pension and postretirement plans adjustment	236	59	423	180
Debt and equity securities - unrealized gain (loss)		(1)		1
Cash flow hedging instruments - unrealized gain (loss)	1	68	39	61
Purchase of subsidiary shares		25		25
Balance at the end of the period	(6,467)	(4,108)	(6,467)	(4,108)
Noncontrolling Interest
Increase (decrease) in equity
Balance at the beginning of the period	37	492	33	446
Net income	2	8	7	42
Other comprehensive income (loss), net of tax:
Cumulative translation adjustment	(1)	(10)	(2)	6
Purchase of subsidiary shares		(457)		(461)
Balance at the end of the period	$ 38	$ 33	$ 38	$ 33