v3.19.1

Stock-based compensation (Restricted stock unity activity) (Details) shares in Thousands	3 Months Ended
	Apr. 30, 2019 $ / shares shares
RSUs and PRSUs
Shares
Unvested, beginning balance (in shares) | shares	648
Granted (in shares) | shares	421
Vested (in shares) | shares	(94)
Forfeited (in shares) | shares	(19)
Unvested, ending balance (in shares) | shares	956
Weighted-average grant date fair value
Unvested, beginning balance (usd per share) | $ / shares	$ 55.20
Granted (usd per share) | $ / shares	73.02
Vested (usd per share) | $ / shares	52.35
Forfeited (usd per share) | $ / shares	54.48
Unvested, ending balance (usd per share) | $ / shares	$ 63.33
RSAs and PRSAs
Shares
Unvested, beginning balance (in shares) | shares	256
Granted (in shares) | shares	0
Vested (in shares) | shares	(11)
Forfeited (in shares) | shares	(10)
Unvested, ending balance (in shares) | shares	235
Weighted-average grant date fair value
Unvested, beginning balance (usd per share) | $ / shares	$ 61.93
Granted (usd per share) | $ / shares	0.00
Vested (usd per share) | $ / shares	62.75
Forfeited (usd per share) | $ / shares	61.72
Unvested, ending balance (usd per share) | $ / shares	$ 61.91

X

- Definition

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

+ References

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=109197908&loc=d3e5070-113901

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X

- 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
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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X

- Definition

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
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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X

- Definition

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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X

- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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X

- Definition

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

+ References

No definition available.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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X

- Definition

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.

+ References

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-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 2
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