Fair Value Measurements - Debt Securities, Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 572,073	$ 566,289
Unrealized Gains	0	79
Unrealized Losses	(8,242)	(6,384)
Total	563,831	559,984
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	127,500	127,500
Unrealized Gains	0	0
Unrealized Losses	(657)	(615)
Total	126,843	126,885
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,911	27,946
Unrealized Gains	0	0
Unrealized Losses	(90)	(85)
Total	25,821	27,861
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	93,978	87,259
Unrealized Gains	0	0
Unrealized Losses	(2,812)	(2,194)
Total	91,166	85,065
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	324,684	323,584
Unrealized Gains	0	79
Unrealized Losses	(4,683)	(3,490)
Total	$ 320,001	$ 320,173

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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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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Amortized cost 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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Amount 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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