Cash and Cash Equivalents, Investments, and Fair Value Measurements - Schedule of Investments (Details) - USD ($) $ in Thousands	Jul. 31, 2024	Jan. 31, 2024
Cash and cash equivalents:
Amortized Cost	$ 205,898	$ 256,651
Short-term investments:
Amortized Cost	502,950	671,897
Gross Unrealized Gains	59	30
Gross Unrealized Losses	(735)	(2,622)
Estimated Fair Value	502,274	669,305
Long-term investments:
Amortized Cost	393,133	188,069
Gross Unrealized Gains	1,419	703
Gross Unrealized Losses	(50)	(115)
Estimated Fair Value	394,502	188,657
Total assets measured at fair value, Amortized Cost	1,101,981	1,116,617
Total assets measured at fair value, Gross Unrealized Gains	1,478	733
Total assets measured at fair value, Gross Unrealized Losses	(785)	(2,737)
Total assets measured at fair value, Estimated Fair Value	1,102,674	1,114,613
Total cash and cash equivalents
Cash and cash equivalents:
Amortized Cost	205,898	256,651
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	205,898	256,651
Level 1 | U.S. Treasury securities
Short-term investments:
Amortized Cost	134,506	234,776
Gross Unrealized Gains	16	0
Gross Unrealized Losses	(105)	(1,053)
Estimated Fair Value	134,417	233,723
Long-term investments:
Amortized Cost	141,343	27,175
Gross Unrealized Gains	791	121
Gross Unrealized Losses	0	0
Estimated Fair Value	142,134	27,296
Level 1 | Cash
Cash and cash equivalents:
Amortized Cost	86,970	43,925
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	86,970	43,925
Level 1 | Money market funds
Cash and cash equivalents:
Amortized Cost	118,928	204,481
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	118,928	204,481
Level 2 | Corporate notes and bonds
Short-term investments:
Amortized Cost	199,574	279,248
Gross Unrealized Gains	20	12
Gross Unrealized Losses	(370)	(1,068)
Estimated Fair Value	199,224	278,192
Long-term investments:
Amortized Cost	214,371	69,970
Gross Unrealized Gains	565	279
Gross Unrealized Losses	(32)	(67)
Estimated Fair Value	214,904	70,182
Level 2 | U.S. agency securities
Short-term investments:
Amortized Cost	168,870	157,873
Gross Unrealized Gains	23	18
Gross Unrealized Losses	(260)	(501)
Estimated Fair Value	168,633	157,390
Long-term investments:
Amortized Cost	37,419	90,924
Gross Unrealized Gains	63	303
Gross Unrealized Losses	(18)	(48)
Estimated Fair Value	$ 37,464	91,179
Level 2 | Certificates of deposit
Cash and cash equivalents:
Amortized Cost		8,245
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		$ 8,245