Recent accounting developments

12 Months Ended

Dec. 31, 2023

Accounting Changes and Error Corrections [Abstract]

Recent accounting developments

27. Recent accounting developments

The following table provides a description of accounting standards that were adopted by the Company in 2023 as well as standards that are not effective that could have an impact to M&T’s consolidated financial statements upon adoption.

Standard	Description	Required date of adoption	Effect on consolidated financial statements
Standards Adopted in 2023
Fair Value Hedging of Multiple Hedge Layers under Portfolio Layer Method	The amendments allow multiple hedged layers to be designated for a single closed portfolio of financial assets or one or more beneficial interests secured by a portfolio of financial instruments. If multiple hedged layers are designated, the amendments require an analysis to be performed to support the expectation that the aggregate amount of the hedged layers is anticipated to be outstanding for the designated hedge periods. Only closed portfolios may be hedged under the portfolio layer method (that is, no assets can be added to the closed portfolio once established), however designating new hedging relationships and dedesignating existing hedging relationships associated with the closed portfolio any time after the closed portfolio is established is permitted.	January 1, 2023	The Company did not have any designated hedging relationships under the portfolio layer method in 2023 and, therefore, the adoption had no impact on its consolidated financial statements.
Accounting for Troubled Debt Restructurings and Expansion of Vintage Disclosures Applicable to Credit Losses	The amendments (1) eliminate the accounting guidance for troubled debt restructurings and require enhanced disclosure for certain loan refinancings by creditors when a borrower is experiencing financial difficulty and (2) require disclosure of current period gross write-offs by year of origination for financing receivables and net investments in leases within credit loss disclosures.	January 1, 2023	The Company adopted the amended guidance effective January 1, 2023 using a prospective transition method and is no longer required to identify troubled debt restructurings and apply specialized accounting to such loans. The Company has complied with the modified disclosure requirements in notes 4 and 5.
Standards Not Yet Adopted as of December 31, 2023
Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method	The amendments permit an election to account for tax equity investments, regardless of the tax credit program from which the income tax credits are received, using the proportional amortization method if certain conditions are met. Under the proportional amortization method, the initial cost of the investment is amortized in proportion to the income tax credits and other income tax benefits received and the net amortization and income tax credits and other income tax benefits are recognized in the income statement as a component of income tax expense (benefit).	January 1, 2024 Early adoption permitted	The Company adopted the amended guidance effective January 1, 2024 using a modified retrospective transition. The guidance did not have a material impact on the Company’s consolidated financial statements.