Financial Instruments: (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivatives	$ (387)	$ (26)
Gain (loss) recognized in earnings attributable to risk being hedged	76	102
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Recognized in OCI	579	12
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, Effective Portion Reclassified from AOCI to Earnings	56	24
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	0	3
Derivative instruments in fair value hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	0	0
Derivative instruments in cash flow hedging relationships
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	0	0
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	360	51
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	219	(37)
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	(20)	(24)
Gain (loss) recognized in earnings attributable to risk being hedged	46	57
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	(13)	(19)
Gain (loss) recognized in earnings attributable to risk being hedged	30	45
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)
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	(1)	2
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	37	20
Gain (Loss) Recognized in Earnings and Other Comprehensive Income, (Ineffectiveness) and Amounts Excluded from Effectiveness Testing	1	1
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	(439)	(81)
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	9	5
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	10	2
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	$ 85	$ 98