Postretirement Benefits (Tables)

12 Months Ended

Mar. 31, 2017

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Schedule of net periodic expense for postretirement welfare benefits

The net periodic expense for our pension plans is as follows:

	U.S. Plans									Non-U.S. Plans
	Years Ended March 31,									Years Ended March 31,
(In millions)	2017			2016			2015			2017			2016			2015
Service cost - benefits earned during the year	$	5		$	4		$	1		$	15		$	20		$	16
Interest cost on projected benefit obligation	13			18			19			23			24			34
Expected return on assets	(15		)	(19		)	(21		)	(26		)	(30		)	(30		)
Amortization of unrecognized actuarial loss and prior service costs	11			42			19			4			3			3
Curtailment/settlement loss (gain)	—			2			—			(2		)	—			6
Net periodic pension expense	$	14		$	47		$	18		$	14		$	17		$	29

The net periodic expense for our postretirement welfare benefits is as follows:

	Years Ended March 31,
(In millions)	2017			2016		2015
Service cost - benefits earned during the year	$	1		$	1	$	1
Interest cost on accumulated benefit obligation	2			4		5
Amortization of unrecognized actuarial gain and prior service credit	(1		)	—		(4		)
Net periodic postretirement expense	$	2		$	5	$	2

Schedule of changes in benefit obligations for postretirement welfare plans

Information regarding the changes in benefit obligations for our postretirement welfare plans is as follows:

	Years Ended March 31,
(In millions)	2017			2016
Benefit obligation at beginning of period	$	98		$	118
Service cost	1			1
Interest cost	2			4
Plan amendments	—			(16		)
Actuarial (gain) / loss	(13		)	3
Benefit payments	(6		)	(11		)
Curtailment gain	—			(1		)
Benefit obligation at end of period	$	82		$	98