Fair Value Measurements - Additional Information (Details) - USD ($)	12 Months Ended
Jan. 31, 2021	Nov. 27, 2017
November 2017 Facility \| Secured Debt
Derivative [Line Items]
Debt instrument, principal amount		$ 350,000,000.0
November 2017 Facility \| Revolving Credit Facility \| Secured Debt \| Wells Fargo Bank
Derivative [Line Items]
Total debt outstanding with carrying amount	$ 30,000,000.0
0.00% Convertible Notes Due 2026 \| Senior Notes
Derivative [Line Items]
Total debt outstanding with carrying amount	$ 267,600,000
Debt instrument interest rate stated percentage	0.00%
Debt instrument maturity year	2026
Debt instrument, principal amount	$ 345,000,000.0
Debt instrument, if-converted value of note less than principal amount	$ 113,100,000
0.00% Convertible Notes Due 2026 \| Senior Notes \| Over the Counter Market
Derivative [Line Items]
Quoted bid price of notes	$ 101.00
0.00% Convertible Notes Due 2026 \| Senior Notes \| Level 2
Derivative [Line Items]
Convertible senior notes, fair value	$ 348,400,000
0.00% Convertible Notes Due 2026 \| Senior Notes \| Class A Common Stock
Derivative [Line Items]
Closing price of common stock	$ 17.34
Interest Rate Swap
Derivative [Line Items]
Derivative, effective date	Sep. 05, 2019
Derivative, maturity period	5 years
Derivative, notional value	$ 30,000,000.0
Net unrealized loss of interest rate swap	$ 1,200,000

Debt instrument, convertible, quoted bid price.

No definition available.

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- Definition

Debt instrument maturity year.

+ References

No definition available.

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- Definition

Net unrealized loss of the interest rate swap.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

No definition available.

+ Details

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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)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031898-161870

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- Definition

Price of the entity's common stock which would be required to be attained for the conversion feature embedded in the debt instrument to become effective.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-SubTopic 10
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-Paragraph 1
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- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

+ References

No definition available.

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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

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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