Fair Value Measurements - Narrative (Details) $ / shares in Units, $ in Thousands	12 Months Ended
Jan. 31, 2022 USD ($) $ / shares
Debt Instrument [Line Items]
Closing price of common stock (in dollars per share) \| $ / shares	$ 197.89
2023 Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount outstanding	$ 17,228
If-converted value in excess of principal	53,300
2025 Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount outstanding	1,059,997
If-converted value in excess of principal	51,600
2026 Notes \| Senior Notes
Debt Instrument [Line Items]
Principal amount outstanding	$ 1,150,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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- Definition

The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Details

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