Commitment amount.

No definition available.

Name:	plx_CommitmentAmount
Namespace Prefix:	plx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Commitments And Contingencies [Line Items]

+ References

No definition available.

+ Details

Name:	plx_CommitmentsAndContingenciesLineItems
Namespace Prefix:	plx_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Required royalty payments represented as a percentage to grants received.

+ References

No definition available.

+ Details

Name:	plx_PercentageOfRoyaltiesToGrantReceived
Namespace Prefix:	plx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of royalties based on sale of products developed from projects funded.

+ References

No definition available.

+ Details

Name:	plx_RoyaltiesOnSaleOfProducts
Namespace Prefix:	plx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15(a))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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

- Details

Name:	us-gaap_TypeOfArrangementAxis=us-gaap_NoncollaborativeArrangementTransactionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis=us-gaap_RoyaltyAgreementTermsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=plx_OfficeOfIsraeliInnovationAuthorityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=plx_OutsideOfIsraelMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

COMMITMENTS (Details) - USD ($)	12 Months Ended
COMMITMENTS (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Arrangement Other than Collaborative [Member]
Commitments And Contingencies [Line Items]
Subcontracting commitment amount	$ 5,300,000
Royalty Agreement Terms [Member] \| Office of the Israeli Innovation Authority [Member]
Commitments And Contingencies [Line Items]
Royalty expense included in cost of revenue	$ 911,000	$ 1,400,000	$ 1,600,000
Minimum [Member] \| Royalty Agreement Terms [Member] \| Office of the Israeli Innovation Authority [Member]
Commitments And Contingencies [Line Items]
Royalties based on sale of products developed from funded projects, percentage	3.00%
Maximum [Member] \| Royalty Agreement Terms [Member] \| Office of the Israeli Innovation Authority [Member]
Commitments And Contingencies [Line Items]
Royalties based on sale of products developed from funded projects, percentage	6.00%
Accrued royalties	$ 39,800,000	$ 40,800,000
Percentage of Royalties to Grant Received	100.00%	100.00%	100.00%
Maximum [Member] \| Royalty Agreement Terms [Member] \| Outside of Israel [Member]
Commitments And Contingencies [Line Items]
Percentage of Royalties to Grant Received	300.00%	300.00%	300.00%