Contingencies: (Combustible Tobacco Products Litigation) (Details) - Combustible Products - claim	381 Months Ended
Sep. 30, 2026	Sep. 30, 2025
Combustible Tobacco Products
Loss Contingencies [Line Items]
Claims filed (in claims)	600
Health Care Cost Recovery Actions
Loss Contingencies [Line Items]
Claims filed (in claims)	7	17
Smoking And Health Class Actions Related To CCAA Plan
Loss Contingencies [Line Items]
Claims released (in claims)	9
Health Care Cost Recovery Actions Related To CCAA Plan
Loss Contingencies [Line Items]
Claims released (in claims)	10

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details