Investments - Additional Information (Details) - USD ($)		3 Months Ended	6 Months Ended
Jun. 10, 2021	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020	Jan. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available-for-sale, realized gain (loss)		$ 0	$ 0	$ 0	$ 0
Purchases of strategic investments	$ 75,000,000			86,900,000	13,000,000
Gain on investments		32,076,000	$ 0	32,076,000	$ 2,538,000
Equity securities		122,364,000		122,364,000		$ 13,538,000
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity securities		$ 107,076,000		$ 107,076,000		$ 0

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

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Amount of realized and unrealized gain (loss) on investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27405-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c),9(a))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Amount of cash outflow to acquire investments classified as other.

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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