Equity, Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 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 income (loss), net of tax	20,576
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	(73)	(169)
Amounts reclassified from accumulated other comprehensive loss	4	7
Net other comprehensive income (loss)	(69)	(162)
Ending balance, accumulated other comprehensive income (loss), net of tax	(1,002)	(529)
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	(81)	(169)
Amounts reclassified from accumulated other comprehensive loss	0	0
Net other comprehensive income (loss)	(81)	(169)
Ending balance, accumulated other comprehensive income (loss), net of tax	(686)	(168)
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	4	7
Net other comprehensive income (loss)	12	7
Ending balance, accumulated other comprehensive income (loss), net of tax	$ (316)	$ (361)