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A general description of the nature of the existing leasing arrangements of a lessor for all operating leases including, but not limited to: (1) guarantees or indemnities; (2) restrictions imposed by lease arrangements; (3) unusual provisions or conditions; (4) contingent rentals; and (5) lease expiration dates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 50
-Paragraph 4
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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

No definition available.

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Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

No definition available.

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Term of the lessor's leasing arrangement renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6787-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Sum of the carrying amounts as of the balance sheet date of amounts paid in advance for expenses which will be charged against earnings in periods after one year or beyond the operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
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Term of the unrecognized unconditional purchase obligation, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 440
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Commitments and contingencies.

No definition available.

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Contractual obligation paid.

No definition available.

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Total aggregate costs related to services rendered to date by an entity.

No definition available.

Name:	xene_CostOfServicesRendered
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Future potential payments.

No definition available.

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License manufacture and supply agreement upfront fee.

No definition available.

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Milestone payments paid.

No definition available.

Name:	xene_MilestonePaymentsPaid
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Upfront fee paid.

No definition available.

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Name:	us-gaap_CounterpartyNameAxis=xene_FirstOrderPharmaceuticalsIncMember
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Name:	us-gaap_CounterpartyNameAxis=xene_FirstOrderPharmaceuticalsIncAndValeantPharmaceuticalsInternationalIncMember
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Name:	us-gaap_TypeOfArrangementAxis=xene_LicenseAgreementMember
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Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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