The amount of milestone payment made under the business combination.

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The amount of probability adjusted milestone payment amount under the business combination.

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Represents the remaining contractual maturities of marketable securities.

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Represents the number of probability adjusted milestone payments.

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No definition available.

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- Definition

The amount of fair value disclosure of warrants.

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No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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-Name Accounting Standards Codification
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- Definition

Value of input used to measure contingent consideration liability from business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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Fair Value Measurements and Marketable Securities (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jul. 31, 2019 USD ($) item	Jan. 31, 2019 USD ($)	Jul. 31, 2018 USD ($)
Assets
Marketable securities	$ 94,003	$ 103,247
Liability
Number of probability adjusted milestone payments \| item	3
Probability adjusted milestone payment amount	$ 200
First milestone payment		$ 200
Fair value assets transfer, level 1 to 2	0		$ 0
Fair value assets transfer, level 2 to 1	0		0
Fair value liabilities transfer, level 1 to 2	0		0
Fair value liabilities transfer, level 2 to 1	0		$ 0
Other-than-temporary impairments	$ 0
Remaining contractual maturities of marketable securities	1 year	1 year
Write-off of contingent consideration	$ 500
Discount rate \| Minimum
Liability
Business combination, measurement input	3
Discount rate \| Maximum
Liability
Business combination, measurement input	3.02
Recurring
Assets
Total cash equivalents	$ 713,953	$ 70,073
Marketable securities	94,003	103,247
Total assets	807,956	173,320
Liability
Contingent consideration related to business combinations		474
Redeemable convertible preferred stock warrant liability		4,537
Total liabilities		5,011
Recurring \| Money market funds
Assets
Total cash equivalents	698,945	42,132
Recurring \| Corporate debt securities
Assets
Total cash equivalents	15,008	27,941
Marketable securities	79,985	91,796
Recurring \| US treasuries
Assets
Marketable securities	14,018	11,451
Level 1 \| Recurring
Assets
Total cash equivalents	698,945	42,132
Marketable securities	14,018	11,451
Total assets	712,963	53,583
Level 1 \| Recurring \| Money market funds
Assets
Total cash equivalents	698,945	42,132
Level 1 \| Recurring \| US treasuries
Assets
Marketable securities	14,018	11,451
Level 2 \| Recurring
Assets
Total cash equivalents	15,008	27,941
Marketable securities	79,985	91,796
Total assets	94,993	119,737
Level 2 \| Recurring \| Corporate debt securities
Assets
Total cash equivalents	15,008	27,941
Marketable securities	$ 79,985	91,796
Level 3 \| Recurring
Liability
Contingent consideration related to business combinations		474
Redeemable convertible preferred stock warrant liability		4,537
Total liabilities		$ 5,011