Fair value of warrant liability.

No definition available.

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Namespace Prefix:	lptx_
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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
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://www.xbrl.org/2003/role/presentationRef
-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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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Balance Type:	debit
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- Details

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- Details

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- Details

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- Details

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- Details

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Warrants - (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Nov. 14, 2017
Warrants
Number of Shares Issuable	3,012,610
Fair value of warrant liability	$ 16,713	$ 11,862	$ 14,344
Loss from change in fair value of warrant liability	$ 4,851
Common Stock \| Equity
Warrants
Number of Shares Issuable	54,516
Exercise price of warrant	$ 0.01
Common Stock \| Liability
Warrants
Number of Shares Issuable	2,958,094
Exercise price of warrant	$ 6.085
Common Stock \| Private placement \| Warrants expires on 2024
Warrants
Number of Shares Issuable			2,958,094
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