Significant accounting policies (Policies)	9 Months Ended
Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Accounting	The consolidated interim financial statements of the Company were compiled in accordance with GAAP using the accounting policies set forth in note 1 of Notes to Financial Statements included in M&T's 2023 Annual Report, except as described in the following table. The financial statements contain all adjustments which are, in the opinion of management, necessary for a fair statement of the Company's financial position, results of operations and cash flows for the interim periods presented.

Disclosure of accounting policy for 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).

No definition available.

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