Fair Value Measurements 2 (Details) - USD ($) $ in Millions		Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Liabilities:
Total debt		$ 2,783	$ 2,791
Facility exit reserve		7	12	$ 19	$ 49
Facility Exit
Liabilities:
Facility exit reserve		7	11	$ 16	$ 21
Carrying Value
Liabilities:
Total debt		2,783	2,791
Carrying Value | Facility Exit
Liabilities:
Facility exit reserve	[1]	7	11
Estimated Fair Value
Liabilities:
Total debt	[2]	2,844	2,903
Estimated Fair Value | Facility Exit
Liabilities:
Facility exit reserve	[1]	$ 8	$ 12

[1] Estimated fair value for the facility exit reserve is determined using the Company’s incremental borrowing rate at March 31, 2018 and 2017. At March 31, 2018 and 2017, the facility exit reserve included approximately $2 million and $3 million, respectively, in “Accrued expenses and other current liabilities” and approximately $5 million and $8 million, respectively, in “Other noncurrent liabilities” in the Company’s Consolidated Balance Sheets (Level 3).

[2] Estimated fair value of total debt is based on quoted prices for similar liabilities for which significant inputs are observable except for certain long-term lease obligations, for which fair value approximates carrying value (Level 2).