Asset Charges and Other Costs (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended					12 Months Ended
	Mar. 31, 2015	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Asset charges -
Goodwill impairment	$ 517					$ 40	$ 517	$ 40	$ 0
Other long-lived asset impairments							78	4	0
Accelerated depreciation on underutilized assets							44	0	0
Total asset charges		$ 58	$ 18	$ 10	$ 553		639	44	0
Other costs (gains) -
Facility closures and severance							88	15	13
Loss on disposal of non-core assets							15	10	0
Mark-to-market impact on currency derivatives not designated as accounting hedges							11	8	1
Merger costs							8	0	0
Gain from remeasurement of prior interest in equity method investment							0	(8)	0
All other costs, net							12	4	78
Total other costs (gains), net							134	29	92
Total asset charges and other costs (gains), net							$ 773	$ 73	$ 92