Cash Equivalents and Short-Term Investments - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2024	Jul. 31, 2023	Jul. 31, 2024	Jul. 31, 2023	Jan. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest and investment income	$ 12,800	$ 9,100	$ 24,900	$ 16,400
Net amortization of premiums or discounts on short-term investments	4,200	(4,900)	9,141	8,494
Contingent consideration liability, current	8,455		8,455		$ 3,608
Change in fair value of acquisition related contingent consideration			3,750	0
Accretion expense	0	0	100	100
Opstrace Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration liability, current	7,400		7,400
Change in fair value of acquisition related contingent consideration	3,800	$ 0		$ 0
Fair Value, Inputs, Level 3 \| Opstrace Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent payment	$ 7,400		$ 7,400		$ 3,600

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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