Fair Value Measurements 2 (Details) - USD ($) $ in Millions		Jun. 30, 2018	Mar. 31, 2018
Liabilities:
Facility exit reserves		$ 100	$ 7
Facility Exit
Liabilities:
Facility exit reserves		40	7
Carrying Value
Liabilities:
Total debt		2,780	2,783
Carrying Value | Facility Exit
Liabilities:
Facility exit reserves	[1]	40	7
Estimated Fair Value
Liabilities:
Total debt	[2]	2,816	2,844
Estimated Fair Value | Facility Exit
Liabilities:
Facility exit reserves	[1]	$ 42	$ 8

[1] Estimated fair value for the facility exit reserves is determined using the Company’s incremental borrowing rate at June 30, 2018 and March 31, 2018. At June 30, 2018 and March 31, 2018, the facility exit reserves included carrying values of approximately $13 million and $2 million, respectively, in “Accrued expenses and other current liabilities” and approximately $27 million and $5 million, respectively, in “Other noncurrent liabilities” in the Company’s Condensed 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).