Share-Based Compensation - Summary of Restricted Stock Awards and Performance-based Restricted Stock Unit Activity (Details)	9 Months Ended
Oct. 31, 2020 $ / shares shares
Restricted Stock Awards
Number of Units/ Shares
Unvested, beginning of period (in shares) \| shares	3,180,016
Granted (in shares) \| shares	2,666,188
Vested (in shares) \| shares	(1,231,074)
Forfeited (in shares) \| shares	(992,683)
Unvested, end of period (in shares) \| shares	3,622,447
Weighted Average Grant Date Fair Value
Unvested, beginning of period (in dollars per share) \| $ / shares	$ 5.47
Granted (in dollars per share) \| $ / shares	3.38
Vested (in dollars per share) \| $ / shares	6.38
Forfeited (in dollars per share) \| $ / shares	4.77
Unvested, end of period (in dollars per share) \| $ / shares	$ 3.81
Restricted Stock Units (RSUs)
Number of Units/ Shares
Unvested, beginning of period (in shares) \| shares	71,740
Granted (in shares) \| shares	108,750
Vested (in shares) \| shares	(16,560)
Forfeited (in shares) \| shares	0
Unvested, end of period (in shares) \| shares	163,930
Weighted Average Grant Date Fair Value
Unvested, beginning of period (in dollars per share) \| $ / shares	$ 5.81
Granted (in dollars per share) \| $ / shares	1.25
Vested (in dollars per share) \| $ / shares	8.76
Forfeited (in dollars per share) \| $ / shares	0
Unvested, end of period (in dollars per share) \| $ / shares	$ 2.49
Performance-Based Restricted Stock Units
Number of Units/ Shares
Unvested, beginning of period (in shares) \| shares	2,042,138
Granted (in shares) \| shares	1,722,187
Vested (in shares) \| shares	(29,320)
Forfeited (in shares) \| shares	(763,359)
Unvested, end of period (in shares) \| shares	2,971,646
Weighted Average Grant Date Fair Value
Unvested, beginning of period (in dollars per share) \| $ / shares	$ 2.48
Granted (in dollars per share) \| $ / shares	2.49
Vested (in dollars per share) \| $ / shares	14.22
Forfeited (in dollars per share) \| $ / shares	3.61
Unvested, end of period (in dollars per share) \| $ / shares	$ 2.11

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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