Segment, Geographical Area, Major Customer and Major Supplier Information (Geographical Information - Net Sales) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 2,789	$ 2,847	$ 2,831	$ 2,680	$ 2,549	$ 2,403	$ 2,414	$ 2,401	$ 11,147	$ 9,767	$ 9,812
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									3,507	3,021	3,350
Asia and Other Pacific [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									2,139	1,845	1,745
Brazil [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									1,750	1,544	1,391
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									144	209	230
Germany [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									2,976	2,449	2,391
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									139	135	53
Other Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales									$ 492	$ 564	$ 652