Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), start of period	$ (1,493)	$ (1,838)	$ (2,035)	$ (1,059)
Other comprehensive income (loss) before reclassifications	(112)	229	429	(563)
Amounts reclassified from accumulated other comprehensive (income) loss	(28)	15	(27)	28
Other comprehensive income (loss)	(140)	244	402	(535)
Accumulated other comprehensive income (loss), end of period	(1,633)	(1,594)	(1,633)	(1,594)
Foreign currency translation
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), start of period	(1,545)	(1,778)	(1,953)	(992)
Other comprehensive income (loss) before reclassifications	(103)	224	305	(562)
Amounts reclassified from accumulated other comprehensive (income) loss	0	0	0	0
Other comprehensive income (loss)	(103)	224	305	(562)
Accumulated other comprehensive income (loss), end of period	(1,648)	(1,554)	(1,648)	(1,554)
Pension and other postretirement benefits
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), start of period	39	(40)	(69)	(31)
Other comprehensive income (loss) before reclassifications	(1)	0	117	0
Amounts reclassified from accumulated other comprehensive (income) loss	(9)	(9)	(19)	(18)
Other comprehensive income (loss)	(10)	(9)	98	(18)
Accumulated other comprehensive income (loss), end of period	29	(49)	29	(49)
Derivative financial instruments
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), start of period	(32)	(109)	(50)	(119)
Other comprehensive income (loss) before reclassifications	(18)	11	(9)	(3)
Amounts reclassified from accumulated other comprehensive (income) loss	1	25	10	49
Other comprehensive income (loss)	(17)	36	1	46
Accumulated other comprehensive income (loss), end of period	(49)	(73)	(49)	(73)
Available-for-sale securities
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income (loss), start of period	45	89	37	83
Other comprehensive income (loss) before reclassifications	10	(6)	16	2
Amounts reclassified from accumulated other comprehensive (income) loss	(20)	(1)	(18)	(3)
Other comprehensive income (loss)	(10)	(7)	(2)	(1)
Accumulated other comprehensive income (loss), end of period	$ 35	$ 82	$ 35	$ 82