Fair Value Measurements (Details) - USD ($) $ in Thousands	Apr. 30, 2023	Jan. 31, 2023
Assets, Fair Value Disclosure
Cash equivalents:	$ 223,274	$ 539,389
Short-term investments	3,292,514	3,067,966
Long-term investments	1,090,715	1,073,023
Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	217,323	520,138
Money market funds \| Revision of Prior Period, Reclassification, Adjustment
Assets, Fair Value Disclosure
Cash equivalents:		141,000
Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	5,951	9,304
Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:		6,903
Certificates of deposit
Assets, Fair Value Disclosure
Cash equivalents:		3,044
Level 1 \| Money market funds \| Revision of Prior Period, Reclassification, Adjustment
Assets, Fair Value Disclosure
Cash equivalents:		141,000
Recurring
Assets, Fair Value Disclosure
Total	4,606,503	4,680,378
Recurring \| Corporate notes and bonds
Assets, Fair Value Disclosure
Short-term investments	1,232,949	1,301,296
Long-term investments	654,691	801,784
Recurring \| Commercial paper
Assets, Fair Value Disclosure
Short-term investments	937,783	881,348
Recurring \| U.S. government and agency securities
Assets, Fair Value Disclosure
Short-term investments	686,462	440,128
Long-term investments	436,024	263,708
Recurring \| Certificates of deposit
Assets, Fair Value Disclosure
Short-term investments	435,320	445,194
Long-term investments		7,531
Recurring \| Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	217,323	520,138
Recurring \| Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	5,951	9,304
Recurring \| Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:		6,903
Recurring \| Certificates of deposit
Assets, Fair Value Disclosure
Cash equivalents:		3,044
Recurring \| Level 1
Assets, Fair Value Disclosure
Total	217,323	520,138
Recurring \| Level 1 \| Corporate notes and bonds
Assets, Fair Value Disclosure
Short-term investments	0	0
Long-term investments	0	0
Recurring \| Level 1 \| Commercial paper
Assets, Fair Value Disclosure
Short-term investments	0	0
Recurring \| Level 1 \| U.S. government and agency securities
Assets, Fair Value Disclosure
Short-term investments	0	0
Long-term investments	0	0
Recurring \| Level 1 \| Certificates of deposit
Assets, Fair Value Disclosure
Short-term investments	0	0
Long-term investments		0
Recurring \| Level 1 \| Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	217,323	520,138
Recurring \| Level 1 \| Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	0	0
Recurring \| Level 1 \| Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:		0
Recurring \| Level 1 \| Certificates of deposit
Assets, Fair Value Disclosure
Cash equivalents:		0
Recurring \| Level 2
Assets, Fair Value Disclosure
Total	4,389,180	4,160,240
Recurring \| Level 2 \| Corporate notes and bonds
Assets, Fair Value Disclosure
Short-term investments	1,232,949	1,301,296
Long-term investments	654,691	801,784
Recurring \| Level 2 \| Commercial paper
Assets, Fair Value Disclosure
Short-term investments	937,783	881,348
Recurring \| Level 2 \| U.S. government and agency securities
Assets, Fair Value Disclosure
Short-term investments	686,462	440,128
Long-term investments	436,024	263,708
Recurring \| Level 2 \| Certificates of deposit
Assets, Fair Value Disclosure
Short-term investments	435,320	445,194
Long-term investments		7,531
Recurring \| Level 2 \| Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	0	0
Recurring \| Level 2 \| Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	$ 5,951	9,304
Recurring \| Level 2 \| Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:		6,903
Recurring \| Level 2 \| Certificates of deposit
Assets, Fair Value Disclosure
Cash equivalents:		$ 3,044

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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