Basis of Presentation	12 Months Ended
Dec. 31, 2023
Accounting Policies [Abstract]
Basis of Presentation	2. Basis of presentation: These consolidated financial statements are presented in U.S. dollars and have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”). The Company has one wholly-owned subsidiary as of December 31, 2023, Xenon Pharmaceuticals USA Inc., which was incorporated in Delaware on December 2, 2016. These consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. All intercompany transactions and balances have been eliminated on consolidation.

The entire disclosure for the basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 235
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//235/tableOfContent

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