Equity, Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Changes in Accumulated Other Comprehensive Income (Loss), By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	$ 20,527
Ending balance, accumulated other comprehensive loss, net of tax	20,339
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income (Loss), By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	(933)	$ (367)
Other comprehensive income (loss) before reclassifications	(190)	(439)
Amounts reclassified from accumulated other comprehensive loss	3	11
Net other comprehensive income (loss)	(187)	(428)
Ending balance, accumulated other comprehensive loss, net of tax	(1,120)	(795)
Foreign Currency Translation Adjustment [Member]
Changes in Accumulated Other Comprehensive Income (Loss), By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	(605)	1
Other comprehensive income (loss) before reclassifications	(198)	(439)
Amounts reclassified from accumulated other comprehensive loss	0	0
Net other comprehensive income (loss)	(198)	(439)
Ending balance, accumulated other comprehensive loss, net of tax	(803)	(438)
Defined Benefit Plans Items [Member]
Changes in Accumulated Other Comprehensive Income (Loss), By Component
Beginning balance, accumulated other comprehensive income (loss), net of tax	(328)	(368)
Other comprehensive income (loss) before reclassifications	8	0
Amounts reclassified from accumulated other comprehensive loss	3	11
Net other comprehensive income (loss)	11	11
Ending balance, accumulated other comprehensive loss, net of tax	$ (317)	$ (357)