SUBSEQUENT EVENTS (Narrative) (Details) - USD ($)	Jul. 24, 2017	Jun. 30, 2017
Seven Point Five Percentage Convertible Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.50%
Subsequent Event [Member] \| Convertible Notes Payable [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount	$ 1,000
Debt Instrument, Convertible, Conversion Price	$ 0.85
Shares Issuable Upon Conversion	1,176
Subsequent Event [Member] \| Seven Point Five Percentage Convertible Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount	$ 10,000,000
Debt Instrument, Interest Rate, Stated Percentage	7.50%
Subsequent Event [Member] \| Four Point Five Percentage Convertible Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount	$ 9,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Subsequent Event [Member] \| Four Point Five Percentage Senior Convertible Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Face Amount	$ 8,550,000
Debt Instrument, Interest Rate, Stated Percentage	4.50%

Represents the shares issuable upon conversion.

No definition available.

Name:	plx_SharesIssuableUponConversion
Namespace Prefix:	plx_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=plx_SevenPointFivePercentageConvertibleNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_ConvertibleNotesPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=plx_FourPointFivePercentageConvertibleNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=plx_FourPointFivePercentageSeniorConvertibleNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: