Total Equity (Components of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Beginning balance	$ (1,447)	$ (733)	$ (1,248)	$ (1,093)
Other comprehensive income (loss) before reclassifications	37	(373)	(130)	(9)
Amounts reclassified from AOCI	(9)	(9)	(41)	(13)
Net other comprehensive income (loss) during the period	28	(382)	(171)	(22)
Ending balance	(1,419)	(1,115)	(1,419)	(1,115)
Foreign Currency Translation Adjustments
Beginning balance	(833)	(150)	(663)	(266)
Other comprehensive income (loss) before reclassifications	(76)	(265)	(246)	(149)
Amounts reclassified from AOCI	0	0	0	0
Net other comprehensive income (loss) during the period	(76)	(265)	(246)	(149)
Ending balance	(909)	(415)	(909)	(415)
Change in Net Unrealized Gains (Losses) on Securities Available for Sale
Beginning balance	(101)	(46)	(73)	(282)
Other comprehensive income (loss) before reclassifications	111	(90)	118	156
Amounts reclassified from AOCI	(11)	(12)	(46)	(22)
Net other comprehensive income (loss) during the period	100	(102)	72	134
Ending balance	(1)	(148)	(1)	(148)
Pension, Postretirement and Other
Beginning balance	(513)	(537)	(512)	(545)
Other comprehensive income (loss) before reclassifications	2	(18)	(2)	(16)
Amounts reclassified from AOCI	2	3	5	9
Net other comprehensive income (loss) during the period	4	(15)	3	(7)
Ending balance	$ (509)	$ (552)	$ (509)	$ (552)