Fair Value Measurements (Details) - USD ($) $ in Thousands	Jul. 31, 2023	Jan. 31, 2023
Assets, Fair Value Disclosure
Cash equivalents:	$ 458,725	$ 539,389
Short-term investments	2,996,941	3,067,966
Long-term investments	1,100,748	1,073,023
Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	409,604	520,138
Money market funds \| Revision of Prior Period, Reclassification, Adjustment
Assets, Fair Value Disclosure
Cash equivalents:		141,000
Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:	22,228	6,903
U.S. government securities
Assets, Fair Value Disclosure
Cash equivalents:	15,992
Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	10,901	9,304
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	4,556,414	4,680,378
Recurring \| Corporate notes and bonds
Assets, Fair Value Disclosure
Short-term investments	1,070,871	1,301,296
Long-term investments	674,774	801,784
Recurring \| U.S. government and agency securities
Assets, Fair Value Disclosure
Short-term investments	828,213	440,128
Long-term investments	417,026	263,708
Recurring \| Commercial paper
Assets, Fair Value Disclosure
Short-term investments	792,065	881,348
Recurring \| Certificates of deposit
Assets, Fair Value Disclosure
Short-term investments	305,792	445,194
Long-term investments	8,948	7,531
Recurring \| Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	409,604	520,138
Recurring \| Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:	22,228	6,903
Recurring \| U.S. government securities
Assets, Fair Value Disclosure
Cash equivalents:	15,992
Recurring \| Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	10,901	9,304
Recurring \| Certificates of deposit
Assets, Fair Value Disclosure
Cash equivalents:		3,044
Recurring \| Level 1
Assets, Fair Value Disclosure
Total	409,604	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 \| U.S. government and agency securities
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 \| Certificates of deposit
Assets, Fair Value Disclosure
Short-term investments	0	0
Long-term investments	0	0
Recurring \| Level 1 \| Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	409,604	520,138
Recurring \| Level 1 \| Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:	0	0
Recurring \| Level 1 \| U.S. government securities
Assets, Fair Value Disclosure
Cash equivalents:	0
Recurring \| Level 1 \| Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	0	0
Recurring \| Level 1 \| Certificates of deposit
Assets, Fair Value Disclosure
Cash equivalents:		0
Recurring \| Level 2
Assets, Fair Value Disclosure
Total	4,146,810	4,160,240
Recurring \| Level 2 \| Corporate notes and bonds
Assets, Fair Value Disclosure
Short-term investments	1,070,871	1,301,296
Long-term investments	674,774	801,784
Recurring \| Level 2 \| U.S. government and agency securities
Assets, Fair Value Disclosure
Short-term investments	828,213	440,128
Long-term investments	417,026	263,708
Recurring \| Level 2 \| Commercial paper
Assets, Fair Value Disclosure
Short-term investments	792,065	881,348
Recurring \| Level 2 \| Certificates of deposit
Assets, Fair Value Disclosure
Short-term investments	305,792	445,194
Long-term investments	8,948	7,531
Recurring \| Level 2 \| Money market funds
Assets, Fair Value Disclosure
Cash equivalents:	0	0
Recurring \| Level 2 \| Corporate notes and bonds
Assets, Fair Value Disclosure
Cash equivalents:	22,228	6,903
Recurring \| Level 2 \| U.S. government securities
Assets, Fair Value Disclosure
Cash equivalents:	15,992
Recurring \| Level 2 \| Commercial paper
Assets, Fair Value Disclosure
Cash equivalents:	$ 10,901	9,304
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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
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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), classified as noncurrent.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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