Fair Value Measurements - Available-for-Sale Marketable Securities (Details) - USD ($) $ in Thousands	Oct. 31, 2022	Jan. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Total marketable securities	$ 253,008	$ 277,397
Unrealized Gain	4	3
Unrealized Loss	(2,613)	(889)
Fair Value	250,399	276,511
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Total marketable securities	52,424	67,770
Unrealized Gain	0	0
Unrealized Loss	(644)	(294)
Fair Value	51,780	67,476
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Total marketable securities	150,200	167,693
Unrealized Gain	4	3
Unrealized Loss	(1,696)	(536)
Fair Value	148,508	167,160
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Total marketable securities	36,977	19,052
Unrealized Gain	0	0
Unrealized Loss	(121)	(19)
Fair Value	36,856	19,033
Foreign government obligations
Debt Securities, Available-for-sale [Line Items]
Total marketable securities	4,790	7,640
Unrealized Gain	0	0
Unrealized Loss	(54)	(33)
Fair Value	4,736	7,607
Supranational securities
Debt Securities, Available-for-sale [Line Items]
Total marketable securities		12,923
Unrealized Gain		0
Unrealized Loss		(1)
Fair Value		12,922
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Total marketable securities	8,617	2,319
Unrealized Gain	0	0
Unrealized Loss	(98)	(6)
Fair Value	$ 8,519	$ 2,313

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Paragraph 2
-Subparagraph (c)
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Amortized cost excluding accrued interest, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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