Financial Instruments (Tables)

9 Months Ended

Dec. 31, 2015

Financial Instruments [Abstract]

Fair Value Of Short-Term Investments

Short-term investments consisted of the following as of December 31, 2015 and March 31, 2015 (in millions):

	As of December 31, 2015									As of March 31, 2015
	Cost or Amortized Cost		Gross Unrealized					Fair Value		Cost or Amortized Cost		Gross Unrealized				Fair Value
			Gains		Losses							Gains		Losses
Corporate bonds	$	579	$	—	$	(1	)	$	578	$	467	$	—	$	—	$	467
U.S. Treasury securities	196		—		(1		)	195		214		—		—		214
U.S. agency securities	154		—		—			154		161		1		—		162
Commercial paper	39		—		—			39		110		—		—		110
Short-term investments	$	968	$	—	$	(2	)	$	966	$	952	$	1	$	—	$	953

Fair Value Of Short-Term Investments By Stated Maturity Date Schedule

The following table summarizes the amortized cost and fair value of our short-term investments, classified by stated maturity as of December 31, 2015 and March 31, 2015 (in millions):

	As of December 31, 2015				As of March 31, 2015
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Short-term investments
Due in 1 year or less	$	441	$	441	$	417	$	417
Due in 1-2 years	306		305		281		281
Due in 2-3 years	221		220		244		245
Due in 3-4 years	—		—		10		10
Short-term investments	$	968	$	966	$	952	$	953