Cash Equivalents and Short-Term Investments (Tables)

6 Months Ended

Jul. 31, 2018

Investments, Debt and Equity Securities [Abstract]

Schedule of Amortized Costs, Unrealized Gains and Losses and Estimated Fair Value of Cash Equivalents and Short-term Investments

The amortized cost, unrealized gain (loss) and estimated fair value of the Company’s cash equivalents and short-term investments as of July 31, 2018 and January 31, 2018 were as follows (in thousands):



	As of July 31, 2018
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value

	(unaudited)
Cash equivalents:
Money market funds	$	155,347	$	—	$	—		$	155,347
Commercial paper	12,237		—		—			12,237
Total cash equivalents	$	167,584	$	—	$	—		$	167,584
Short-term investments:
Commercial paper	$	56,191	$	—	$	—		$	56,191
U.S. treasury securities	248,081		—		(217		)	247,864
Corporate debt securities	39,352		6		(39		)	39,319
Total short-term investments	343,624		6		(256		)	343,374
Total	$	511,208	$	6	$	(256	)	$	510,958



	As of January 31, 2018
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash equivalents:
Money market funds	$	90,770	$	—	$	—		$	90,770
Total cash equivalents	$	90,770	$	—	$	—		$	90,770
Short-term investments:
Commercial paper	$	15,946	$	—	$	—		$	15,946
U.S. treasury securities	61,896		—		(158		)	61,738
Corporate debt securities	24,125		—		(44		)	24,081
Total short-term investments	101,967		—		(202		)	101,765
Total	$	192,737	$	—	$	(202	)	$	192,535

Schedule of Contractual Maturities of Short-term Investments

The following tables present the contractual maturities of the Company’s short-term investments as of July 31, 2018 and January 31, 2018 (in thousands):



	As of July 31, 2018				As of January 31, 2018
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value

	(unaudited)
Due within one year	$	328,694	$	328,460	$	93,421	$	93,237
Due between one to five years	14,930		14,914		8,546		8,528
	$	343,624	$	343,374	$	101,967	$	101,765