Equity, Changes in Accumulated Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Changes in Accumulated Other Comprehensive Income, By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	$ 350
Net other comprehensive income (loss)	(73)	13
Ending balance, accumulated other comprehensive income (loss), net of tax	277
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income, By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	350	108
Other comprehensive income (loss) before reclassifications	(69)	10
Amounts reclassified from accumulated other comprehensive income	(4)	3
Net other comprehensive income (loss)	(73)	13
Ending balance, accumulated other comprehensive income (loss), net of tax	277	121
Foreign Currency Translation Adjustment [Member]
Changes in Accumulated Other Comprehensive Income, By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	408	665
Other comprehensive income (loss) before reclassifications	(74)	(204)
Amounts reclassified from accumulated other comprehensive income	0	0
Net other comprehensive income (loss)	(74)	(204)
Ending balance, accumulated other comprehensive income (loss), net of tax	334	461
Defined Benefit Plans Items [Member]
Changes in Accumulated Other Comprehensive Income, By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	(58)	(558)
Other comprehensive income (loss) before reclassifications	0	213
Amounts reclassified from accumulated other comprehensive income	(2)	5
Net other comprehensive income (loss)	(2)	218
Ending balance, accumulated other comprehensive income (loss), net of tax	(60)	(340)
Gains (Losses) on Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income, By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	0	1
Other comprehensive income (loss) before reclassifications	5	1
Amounts reclassified from accumulated other comprehensive income	(2)	(2)
Net other comprehensive income (loss)	3	(1)
Ending balance, accumulated other comprehensive income (loss), net of tax	$ 3	$ 0