Fair Value Measurements (Details) - USD ($) $ in Thousands	Apr. 30, 2026	Jan. 31, 2026
Financial Assets:
Cash equivalents	$ 474,148	$ 763,410
Marketable securities	6,830,037	6,544,031
Privately held debt securities included in strategic investments	3,978	3,968
Total financial assets	7,308,163	7,311,409
U.S. government agency securities
Financial Assets:
Marketable securities	5,590,416	5,383,887
Agency bonds
Financial Assets:
Marketable securities	1,195,153	1,095,471
Treasury bills
Financial Assets:
Marketable securities	44,468	64,673
Money market funds
Financial Assets:
Cash equivalents	470,662	724,236
Treasury bills
Financial Assets:
Cash equivalents		16,876
Agency bonds
Financial Assets:
Cash equivalents	3,486	22,298
Level 1
Financial Assets:
Cash equivalents	470,662	724,236
Marketable securities	0	0
Privately held debt securities included in strategic investments	0	0
Total financial assets	470,662	724,236
Level 1 \| U.S. government agency securities
Financial Assets:
Marketable securities	0	0
Level 1 \| Agency bonds
Financial Assets:
Marketable securities	0	0
Level 1 \| Treasury bills
Financial Assets:
Marketable securities	0	0
Level 1 \| Money market funds
Financial Assets:
Cash equivalents	470,662	724,236
Level 1 \| Treasury bills
Financial Assets:
Cash equivalents		0
Level 1 \| Agency bonds
Financial Assets:
Cash equivalents	0	0
Level 2
Financial Assets:
Cash equivalents	3,486	39,174
Marketable securities	6,830,037	6,544,031
Privately held debt securities included in strategic investments	0	0
Total financial assets	6,833,523	6,583,205
Level 2 \| U.S. government agency securities
Financial Assets:
Marketable securities	5,590,416	5,383,887
Level 2 \| Agency bonds
Financial Assets:
Marketable securities	1,195,153	1,095,471
Level 2 \| Treasury bills
Financial Assets:
Marketable securities	44,468	64,673
Level 2 \| Money market funds
Financial Assets:
Cash equivalents	0	0
Level 2 \| Treasury bills
Financial Assets:
Cash equivalents		16,876
Level 2 \| Agency bonds
Financial Assets:
Cash equivalents	3,486	22,298
Level 3
Financial Assets:
Cash equivalents	0	0
Marketable securities	0	0
Privately held debt securities included in strategic investments	3,978	3,968
Total financial assets	3,978	3,968
Level 3 \| U.S. government agency securities
Financial Assets:
Marketable securities	0	0
Level 3 \| Agency bonds
Financial Assets:
Marketable securities	0	0
Level 3 \| Treasury bills
Financial Assets:
Marketable securities	0	0
Level 3 \| Money market funds
Financial Assets:
Cash equivalents	0	0
Level 3 \| Treasury bills
Financial Assets:
Cash equivalents		0
Level 3 \| Agency bonds
Financial Assets:
Cash equivalents	$ 0	$ 0

Fair value portion of asset recognized for present right to economic benefit.

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