Stock Option Plans - Schedule of Restricted Stock Activity (Details) - Restricted stock awards - $ / shares	12 Months Ended
Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Number of Restricted Stock Units
Number of Restricted Stock Units Outstanding Beginning of Period (in shares)	35,058,103
Granted (in shares)	36,075,434
Canceled (in shares)	(9,276,310)
Vested and converted to shares (in shares)	(23,273,233)
Number of Restricted Stock Units Outstanding End of Period (in shares)	38,583,994	35,058,103
Weighted- Average Grant Date Fair Value Per Share
Weighted- Average Grant Date Fair Value Per Share Beginning of Period (in dollars per share)	$ 13.25
Granted (in dollars per share)	8.96	$ 12.08	$ 16.93
Canceled (in dollars per share)	12.49
Vested and converted to shares (in dollars per share)	11.15
Weighted- Average Grant Date Fair Value Per Share End of Period (in dollars per share)	$ 10.85	$ 13.25

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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.

+ References

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-Publisher FASB
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-Topic 718
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-Section 50
-Paragraph 2
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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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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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).

+ References

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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.

+ References

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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.

+ References

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-Publisher FASB
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- Definition

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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