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Debt 1 (Details) - USD ($) $ in Millions	Mar. 31, 2016	Mar. 31, 2015	Aug. 16, 2013
Debt obligations
Other indebtedness, primarily capital leases	$ 15	$ 17
Unamortized debt issuance costs	(8)	(6)
Unamortized discount for Senior Notes	(4)	(4)
Total debt outstanding	1,953	1,257
Less the current portion	(6)	(10)
Total long-term debt portion	1,947	1,247
Revolving Credit Facility
Debt obligations
Long-term debt	0	0
5.375% Senior Notes due December 2019
Debt obligations
Long-term debt	750	750
3.600% Senior Notes due August 2020
Debt obligations
Long-term debt	400	0
2.875% Senior Notes due August 2018
Debt obligations
Long-term debt	250	250
Unamortized discount for Senior Notes			$ (1)
4.500% Senior Notes due August 2023
Debt obligations
Long-term debt	250	250
Unamortized discount for Senior Notes			$ (1)
Term Loan due April 2022
Debt obligations
Long-term debt	$ 300	$ 0