Leases - Other information (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Leases [Abstract]
Weighted average remaining lease term	5 years 1 month 6 days
Weighted average discount rate	7.90%
Cash paid for amounts included in the measurement of operating lease liabilities	$ 23.4	$ 26.4
Right-of-use assets obtained in exchange for lease obligations	$ 4.6	$ 1.8

No definition available.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

+ Details

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 4
-Subparagraph (g)(3)
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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

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+ Details

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