Document and Entity Information |
12 Months Ended |
|---|---|
Dec. 31, 2025 | |
| Cover [Abstract] | |
| Document Type | 6-K |
| Document Period End Date | Dec. 31, 2025 |
| Amendment Flag | false |
| Entity Registrant Name | CANADIAN NATIONAL RAILWAY CO |
| Entity Central Index Key | 0000016868 |
| Current Fiscal Year End Date | --12-31 |
| Document Fiscal Year Focus | 2025 |
| Document Fiscal Period Focus | FY |
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- Definition Boolean flag that is true when the XBRL content amends previously-filed or accepted submission. No definition available.
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- Definition End date of current fiscal year in the format --MM-DD. No definition available.
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- Definition Fiscal period values are FY, Q1, Q2, and Q3. 1st, 2nd and 3rd quarter 10-Q or 10-QT statements have value Q1, Q2, and Q3 respectively, with 10-K, 10-KT or other fiscal year statements having FY. No definition available.
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- Definition This is focus fiscal year of the document report in YYYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006. No definition available.
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- Definition For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD. No definition available.
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- Definition The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'. No definition available.
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- Definition A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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