Financial Instruments

6 Months Ended

Sep. 30, 2017

Financial Instruments [Abstract]

Financial Instruments

(3) FINANCIAL INSTRUMENTS

Cash and Cash Equivalents

As of September 30, 2017 and March 31, 2017, our cash and cash equivalents were $2,067 million and $2,565 million, respectively. Cash equivalents were valued using quoted market prices or other readily available market information.

Short-Term Investments

Short-term investments consisted of the following as of September 30, 2017 and March 31, 2017 (in millions):

	As of September 30, 2017									As of March 31, 2017
	Cost or Amortized Cost		Gross Unrealized					Fair Value		Cost or Amortized Cost		Gross Unrealized					Fair Value
			Gains		Losses							Gains		Losses
Corporate bonds	$	1,235	$	—	$	(1	)	$	1,234	$	944	$	—	$	(1	)	$	943
U.S. Treasury securities	410		—		(1		)	409		414		—		(1		)	413
U.S. agency securities	132		—		(1		)	131		152		—		(1		)	151
Commercial paper	268		—		—			268		212		—		—			212
Foreign government securities	101		—		—			101		113		—		—			113
Asset-backed securities	119		—		—			119		135		—		—			135
Certificates of deposit	26		—		—			26		—		—		—			—
Short-term investments	$	2,291	$	—	$	(3	)	$	2,288	$	1,970	$	—	$	(3	)	$	1,967

The following table summarizes the amortized cost and fair value of our short-term investments, classified by stated maturity as of September 30, 2017 and March 31, 2017 (in millions):

	As of September 30, 2017				As of March 31, 2017
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Short-term investments
Due within 1 year	$	1,592	$	1,591	$	1,237	$	1,236
Due 1 year through 5 years	696		694		721		719
Due after 5 years	3		3		12		12
Short-term investments	$	2,291	$	2,288	$	1,970	$	1,967