Financial Instruments: (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	$ 226	$ 438	$ 186	$ 816
Gain (loss) recognized in earnings attributable to risk being hedged	35	(281)	50	(241)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Recognized in OCI	(190)	532	42	(174)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	112	(167)	246	(494)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	6	(6)	12	(12)
Foreign exchange contracts | Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Recognized in OCI	(54)	295	65	(159)
Foreign exchange contracts | Derivative instruments in net investment hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Recognized in OCI	(136)	237	(23)	(15)
Cost of financing | Interest rate contracts | Derivative instruments in fair value hedging relationships
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income, recognized on derivative instruments in fair value hedges	13	204	68	263
Gain (loss) recognized in earnings attributable to risk being hedged	19	(166)	27	(142)
Interest expense | Interest rate contracts | Derivative instruments in fair value hedging relationships
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income, recognized on derivative instruments in fair value hedges	11	141	58	183
Gain (loss) recognized in earnings attributable to risk being hedged	16	(115)	23	(99)
Interest expense | Interest rate contracts | Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	(2)	(2)	(6)	(6)
Interest expense | Foreign exchange contracts | Derivative instruments in net investment hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	6	(4)	9	(10)
Other (income) and expense | Foreign exchange contracts | Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	102	(86)	209	(256)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	0	(2)	3	(2)
Other (income) and expense | Foreign exchange contracts | Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	148	183	(56)	388
Other (income) and expense | Warrants | Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives		10		10
Cost of sales | Foreign exchange contracts | Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	6	(60)	22	(163)
Selling, general and administrative expense | Foreign exchange contracts | Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	5	(19)	21	(70)
Selling, general and administrative expense | Equity contracts | Derivative instruments not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	$ 54	$ (100)	$ 116	$ (28)