Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Jan. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 116,275	$ 102,845
Gross Unrealized Gains	0	7
Gross Unrealized Losses	(335)	(24)
Estimated fair value	115,940	102,828
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,343	23,171
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated fair value	15,343	23,171
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	91,735	79,674
Gross Unrealized Gains	0	7
Gross Unrealized Losses	(303)	(24)
Estimated fair value	91,432	$ 79,657
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,197
Gross Unrealized Gains	0
Gross Unrealized Losses	(32)
Estimated fair value	$ 9,165

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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