v3.19.1

Supplemental financial statement information (Other investments) (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018	Jan. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Marketable equity securities, at fair value	$ 77,356		$ 0
Non-marketable equity securities	500		500
Equity method investments	209		209
Total equity investments	78,065		$ 709
Unrealized gain on marketable equity securities	$ 23,511	$ 0

X

- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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X

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1A
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X

- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
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X

- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

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-Name Accounting Standards Codification
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X

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No definition available.

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