Derivative Financial Instruments (Warrant Liability) (Details)	9 Months Ended
Mar. 31, 2017 $ / shares $ / Unit
Warrant [Member]
Method used	Lattice model
Equivalent volatility	61.47%
Equivalent interest rate	0.95%
Floor \| $ / Unit	1.15
Stock price	$ 2.74
Probability price less than strike price	5.80%
Fair value of call	$ 1.55
Probability of fundamental transaction occuring	0.00%
Exercise 2/15/2017 [Member]
Method used	Lattice model
Equivalent volatility	55.28%
Equivalent interest rate	0.80%
Floor \| $ / Unit	1.15
Stock price	$ 2.08
Probability price less than strike price	24.10%
Fair value of call	$ .93
Probability of fundamental transaction occuring	0.00%
Exercise 2/21/2017 [Member]
Method used	Lattice model
Equivalent volatility	55.02%
Equivalent interest rate	0.75%
Floor \| $ / Unit	1.15
Stock price	$ 2.25
Probability price less than strike price	24.10%
Fair value of call	$ 1.08
Probability of fundamental transaction occuring	0.00%
2/23/2017 [Member]
Method used	Lattice model
Equivalent volatility	54.17%
Equivalent interest rate	0.75%
Floor \| $ / Unit	1.15
Stock price	$ 2.27
Probability price less than strike price	23.90%
Fair value of call	$ 1.09
Probability of fundamental transaction occuring	0.00%
3/16/2017 [Member]
Method used	Lattice model
Equivalent volatility	56.93%
Equivalent interest rate	0.95%
Floor \| $ / Unit	1.15
Stock price	$ 2.41
Probability price less than strike price	13.40%
Fair value of call	$ 1.23
Probability of fundamental transaction occuring	0.00%
3/29/2017 [Member]
Method used	Lattice model
Equivalent volatility	61.04%
Equivalent interest rate	0.95%
Floor \| $ / Unit	1.15
Stock price	$ 2.62
Probability price less than strike price	13.80%
Fair value of call	$ 1.44
Probability of fundamental transaction occuring	0.00%

The probability that price is less than strike.

No definition available.

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

- Definition

Floor rate on a price risk derivative such as a floor or a collar. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeFloorPrice
Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Definition

Describes how an entity determines the fair values of its derivatives, including its valuation methodology and significant assumptions used.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

Reference 2: 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.(n))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=68058157&loc=d3e18780-107790

+ Details

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Price at which a dealer is willing to buy an instrument, used as an input to measure fair value.

+ References

+ Details

Name:	us-gaap_FairValueInputsOfferedQuotes
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.

+ References

+ Details

Name:	us-gaap_FairValueInputsProbabilityOfDefault
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=us-gaap_WarrantMember
Namespace Prefix:
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- Details

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- Details

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- Details

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- Details

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