Supplemental Equity and Comprehensive Income Information (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss)
Balance at Beginning of Period	$ (6,289)	$ (3,913)
Other comprehensive income (loss), before tax:
Amounts before reclassification	116	16
Amounts reclassified out	97	85
Total other comprehensive income (loss), before tax	213	101
Tax effect	(245)	(29)
Total other comprehensive income (loss), net of tax	(32)	72
Balance at End of Period	(6,321)	(3,841)
Cumulative Translation Adjustment
Accumulated Other Comprehensive Income (Loss)
Balance at Beginning of Period	(1,095)	(188)
Other comprehensive income (loss), before tax:
Amounts before reclassification	(44)	5
Amounts reclassified out	0	0
Total other comprehensive income (loss), before tax	(44)	5
Tax effect	(149)	3
Total other comprehensive income (loss), net of tax	(193)	8
Balance at End of Period	(1,288)	(180)
Gains (losses) associated with defined benefit pension and postretirement plans amortization
Accumulated Other Comprehensive Income (Loss)
Balance at Beginning of Period	(5,293)	(3,715)
Other comprehensive income (loss), before tax:
Amounts before reclassification	24	0
Amounts reclassified out	124	91
Total other comprehensive income (loss), before tax	148	91
Tax effect	(57)	(30)
Total other comprehensive income (loss), net of tax	91	61
Balance at End of Period	(5,202)	(3,654)
Debt and equity security gains (losses)
Accumulated Other Comprehensive Income (Loss)
Balance at Beginning of Period	0	(2)
Other comprehensive income (loss), before tax:
Amounts before reclassification	0	2
Amounts reclassified out	0	0
Total other comprehensive income (loss), before tax	0	2
Tax effect	0	(1)
Total other comprehensive income (loss), net of tax	0	1
Balance at End of Period	0	(1)
Cash flow hedging instruments gains (losses)
Accumulated Other Comprehensive Income (Loss)
Balance at Beginning of Period	99	(8)
Other comprehensive income (loss), before tax:
Amounts before reclassification	136	9
Amounts reclassified out	(27)	(6)
Total other comprehensive income (loss), before tax	109	3
Tax effect	(39)	(1)
Total other comprehensive income (loss), net of tax	70	2
Balance at End of Period	$ 169	$ (6)