The number of warrants exercised during the period.

No definition available.

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Namespace Prefix:	lptx_
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Balance Type:	na
Period Type:	duration

- Definition

Fair value of warrant liability.

+ References

No definition available.

+ Details

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Namespace Prefix:	lptx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109262497&loc=d3e20148-110875

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

+ Details

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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=us-gaap_LiabilityMember
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- Details

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Warrants - (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Feb. 05, 2019	Nov. 14, 2017
Warrants
Number of Shares Issuable	2,812,610
Number of warrants exercised	200,000
Proceeds from exercise of warrants	$ 1,217
Fair value of warrant liability	3,448	$ 11,862		$ 12,335
Less change in fair value of warrant liability	7,284	473
Other income (expense)
Warrants
Less change in fair value of warrant liability	$ 7,284	$ 473
Common Stock \| Equity
Warrants
Number of Shares Issuable	54,516
Exercise price of warrant	$ 0.01
Common Stock \| Liability
Warrants
Number of Shares Issuable	2,758,094
Exercise price of warrant	$ 6.085
Common Stock \| Private Placement \| Warrants expires on 2024
Warrants
Number of Shares Issuable				2,958,094
Common Stock \| Public Offering \| Subsequent Events
Warrants
Number of Shares Issuable			7,557,142
Warrant Liability \| Subsequent Events
Warrants
Exercise price of warrant			$ 1.95
Warrant Liability \| Private Placement
Warrants
Exercise price of warrant				$ 6.085
Warrant Liability \| Private Placement \| Warrants expires on 2024
Warrants
Exercise price of warrant				$ 6.085
Warrant Liability \| Public Offering \| Subsequent Events
Warrants
Exercise price of warrant			$ 1.75