Cash Equivalents and Short-term Investments (Tables)

12 Months Ended

Jan. 31, 2020

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 January 31, 2020 and 2019 were as follows (in thousands):



	As of January 31, 2020
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash equivalents:
Money market funds	$	416,584	$	—	$	—		$	416,584
U.S. treasury securities	19,996		—		—			19,996
Total cash equivalents	436,580		—		—			436,580
Short-term investments:
U.S. treasury securities	575,920		686		(8		)	576,598
Corporate debt securities	305,859		519		—			306,378
Total short-term investments	881,779		1,205		(8		)	882,976
Total	$	1,318,359	$	1,205	$	(8	)	$	1,319,556



	As of January 31, 2019
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash equivalents:
Money market funds	$	247,426	$	—	$	—		$	247,426
Corporate debt securities	3,409		—		(1		)	3,408
Total cash equivalents	250,835		—		(1		)	250,834
Short-term investments:
U.S. treasury securities	195,913		37		(53		)	195,897
Corporate debt securities	69,483		13		(19		)	69,477
Total short-term investments	265,396		50		(72		)	265,374
Total	$	516,231	$	50	$	(73	)	$	516,208

Schedule of Contractual Maturities of Short-term Investments

The Company's short-term investments as of January 31, 2020 and 2019 all mature within one year, as follows (in thousands):



	As of January 31, 2020				As of January 31, 2019
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due within one year	$	881,779	$	882,976	$	265,396	$	265,374