Equity (Details 6) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated other comprehensive loss
Balance at the beginning of the period	$ (475)	$ (413)	$ (190)
Gains (losses) on cash-flow hedges, net of income tax effect of $29, $25 and $19 for the year ended 2013, 2012 and 2011, respectively	(64)	43	29
Amount of (gains) losses on cash-flow hedges reclassified to earnings, net of income tax effect of $19, $15 and $61 for the year ended 2013, 2012 and 2011 respectively	41	(25)	(105)
Actuarial gains (losses) on pension and postretirement obligations, settlements and plan amendments, net of income tax of $32, $27 and $4 for the year ended 2013, 2012 and 2011, respectively	63	(56)	(10)
Losses (gains) related to pension and other postretirement obligations reclassified to earnings, net of income tax effect of $3, $2 and $5, respectively	5	5	(11)
Unrealized gain on investment, net of income tax effect	1
Currency translation adjustment	(154)	(29)	(126)
Balance at end of the period	(583)	(475)	(413)
Income tax effect of accumulated other comprehensive gain (loss)
Gains (losses) on cash-flow hedges, income tax effect	(29)	25	19
Amount of (gains) losses on cash flow hedges reclassified to earnings, income tax effect	(19)	15	61
Actuarial gains (losses) on pension and other postretirement obligations, settlements and plan amendments, income tax effect	32	(27)	(4)
Losses (gains) related to pension and other postretirement obligations reclassified to earnings, income tax effect	(3)	(2)	5
Cumulative Translation Adjustment
Accumulated other comprehensive loss
Balance at the beginning of the period	(335)	(306)	(180)
Currency translation adjustment	(154)	(29)	(126)
Balance at end of the period	(489)	(335)	(306)
Deferred Gain/(Loss) on Hedging Activities
Accumulated other comprehensive loss
Balance at the beginning of the period	(17)	(35)	41
Gains (losses) on cash-flow hedges, net of income tax effect of $29, $25 and $19 for the year ended 2013, 2012 and 2011, respectively	(64)	43	29
Amount of (gains) losses on cash-flow hedges reclassified to earnings, net of income tax effect of $19, $15 and $61 for the year ended 2013, 2012 and 2011 respectively	41	(25)	(105)
Balance at end of the period	(40)	(17)	(35)
Income tax effect of accumulated other comprehensive gain (loss)
Gains (losses) on cash-flow hedges, income tax effect	(29)	25	19
Amount of (gains) losses on cash flow hedges reclassified to earnings, income tax effect	(19)	15	61
Pension/Postretirement Adjustment
Accumulated other comprehensive loss
Balance at the beginning of the period	(121)	(70)	(49)
Actuarial gains (losses) on pension and postretirement obligations, settlements and plan amendments, net of income tax of $32, $27 and $4 for the year ended 2013, 2012 and 2011, respectively	63	(56)	(10)
Losses (gains) related to pension and other postretirement obligations reclassified to earnings, net of income tax effect of $3, $2 and $5, respectively	5	5	(11)
Balance at end of the period	(53)	(121)	(70)
Income tax effect of accumulated other comprehensive gain (loss)
Actuarial gains (losses) on pension and other postretirement obligations, settlements and plan amendments, income tax effect	32	(27)	(4)
Losses (gains) related to pension and other postretirement obligations reclassified to earnings, income tax effect	(3)	(2)	5
Unrealized Gain (Loss) on Investment
Accumulated other comprehensive loss
Balance at the beginning of the period	(2)	(2)	(2)
Unrealized gain on investment, net of income tax effect	1	0	0
Balance at end of the period	$ (1)	$ (2)	$ (2)