Shareowners' Equity and Noncontrolling Interest (Summary of Changes in Shareowners' Equity and Noncontrolling Interest) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Shareowners' Equity, beginning of period	$ 29,610	$ 27,579
Noncontrolling interest, beginning of period	1,811	1,590
Total Equity, beginning of period	31,421	29,169
Net income, Shareowners' Equity	1,297	1,386
Net Income, Noncontrolling Interest	71	82
Net income, Total Equity	1,368	1,468
Total other comprehensive income (loss), Shareowners' Equity	588	1
Total other comprehensive income (loss), Noncontrolling Interest	33	25
Total other comprehensive income (loss)	621	26
Total comprehensive income for the period, Shareowners' Equity	1,885	1,387
Total comprehensive income for the period, Noncontrolling Interest	104	107
Total comprehensive income for the period, Total Equity	1,989	1,494
Common Stock issued under employee plans	71	79
Common Stock repurchased	25	933
Dividends on Common Stock	535	505
Dividends on ESOP Common Stock	18	18
Dividends attributable to noncontrolling interest	66	48
Noncontrolling Interest, Increase from Capital Contributions	120	43
Sale of subsidiary shares from noncontrolling interest, net	2	1
Non-controlling interest, decrease from disposition of non-controlling interest	8	0
Redeemable noncontrolling interest fair value adjustment	2	0
Other	(27)	8
Shareowners' Equity, end of period	30,534	27,594
Noncontrolling interest, end of period	1,958	1,678
Total Equity, end of period	32,492	29,272
Shareowners' Equity
Sale of subsidiary shares from noncontrolling interest, net	1	0
Redeemable noncontrolling interest fair value adjustment	2	0
Other	(29)	(5)
Noncontrolling Interest
Sale of subsidiary shares from noncontrolling interest, net	1	1
Redeemable noncontrolling interest fair value adjustment	0	0
Other	2	$ 13
Accounting Standards Update 2014-09 [Member]
Net income, Shareowners' Equity	8
Other	$ 480