Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2025
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Nature of Operations Mid Penn Bancorp, Inc. ("Mid Penn" or the "Corporation"), through operations conducted by Mid Penn Bank (the "Bank") and its nonbank subsidiaries, engages in a full-service commercial banking and trust business, making available to the community a wide range of financial services, including, but not limited to, mortgage and home equity loans, secured and unsecured commercial and consumer loans, lines of credit, construction financing, farm loans, community development loans, loans to non-profit entities and local government loans, and various types of time and demand deposits including but not limited to, checking accounts, savings accounts, clubs, money market deposit accounts, certificates of deposit, and Individual Retirement Accounts. In addition, the Bank provides a full range of trust and wealth management services through its Trust Department. Deposits are insured by the Federal Deposit Insurance Corporation ("FDIC") to the extent provided by law. Mid Penn also fulfills the insurance needs of both existing and potential customers through MPB Risk Services, LLC, doing business as MPB Insurance and Risk Management. The financial services are provided to individuals, partnerships, non-profit organizations, and corporations through its retail banking offices located throughout Pennsylvania and three counties in New Jersey. Basis of Presentation For all periods presented, the accompanying consolidated financial statements include the accounts of Mid Penn Bancorp, Inc., its wholly-owned subsidiary, Mid Penn Bank, and five wholly-owned nonbank subsidiaries, MPB Realty, LLC, MPB Financial Services, LLC, which includes MPB Wealth Management, LLC (which ceased operating during the first quarter of 2024), MPB Risk Services, LLC, and MPB Launchpad Fund I, LLC. As of March 31, 2025, the accounts and activities of these nonbank subsidiaries were not material to warrant separate disclosure or segment reporting. As a result, Mid Penn has only one reportable segment for financial reporting purposes. All material intercompany accounts and transactions have been eliminated in consolidation. Certain information and disclosures normally included in consolidated financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. Mid Penn believes the information presented is not misleading, and the disclosures are adequate. For comparative purposes, the March 31, 2024 and December 31, 2024 balances have been reclassified, when necessary, to conform to the 2025 presentation. Such reclassifications had no impact on net income or total shareholders’ equity. In the opinion of management, all adjustments necessary for fair presentation of the periods presented have been reflected in the accompanying consolidated financial statements. All such adjustments are of a normal, recurring nature. These unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the 2024 Annual Report. Subsequent Events Mid Penn has evaluated events and transactions occurring subsequent to the balance sheet date of March 31, 2025 for items that should potentially be recognized or disclosed in these consolidated financial statements. The evaluation was conducted through the issuance date of these consolidated financial statements. On April 30, 2025, Mid Penn completed its acquisition of William Penn Bancorporation through the merger of William Penn with and into Mid Penn. The Merger was completed in accordance with the terms and conditions of the Agreement and Plan of Merger dated October 31, 2024, between Mid Penn and William Penn. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could materially differ from those estimates. Material estimates subject to significant change include the allowance for credit losses, the expected cash flows and collateral values associated with loans that are individually evaluated for credit losses, the carrying value of other real estate owned ("OREO"), the fair value of financial instruments, business combination fair value computations, the valuation of goodwill and other intangible assets, stock-based compensation and deferred income tax assets. Accounting Standards adopted and Updated Significant Accounting Policy Accounting Standards Pending Adoption ASU 2023-06: The FASB issued ASU 2023-06, Disclosure Improvements - Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. ASU 2023-06 amends the ASC to incorporate certain disclosure requirements from SEC Release No. 33-10532 - Disclosure Update and Simplification that was issued in 2018. The effective date for each amendment will be the date on which the SEC’s removal of that related disclosure from Regulation S-X or Regulation S-K becomes effective, with early adoption prohibited. ASU 2023-06 is not expected to have a significant impact on the Corporation's financial statements. ASU 2023-09: The FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. ASU 2023-09 amends the ASC to enhance income tax disclosures by requiring entities to disclose income taxes paid (net of refunds received) disaggregated by federal, state and foreign taxes. Additionally, entities are required to disclose amounts greater than 5% of the total income taxes paid to an individual jurisdiction The amendments are effective for annual periods beginning after December 15, 2024. ASU 2023-09 is not expected to have a significant impact on the Corporation's financial statements. ASU 2024-01—The FASB issued ASU 2024-01, Compensation - Stock Compensation (Topic 718): Scope application of profits interest and similar awards. The amendments in the ASU apply to all reporting entities that account for profits interest awards as compensation to employees or nonemployees in return for goods or services. The amendments are effective for annual periods beginning after December 15, 2025, and interim periods within those annual periods. ASU 2024-01 is not expected to have a significant impact on the Corporation's financial statements. ASU 2024-02: The FASB issued ASU 2024-02, Codification Improvements—Amendments to Remove References to the Concepts Statements. This ASU contains amendments to the Codification that remove references to various FASB Concepts Statements. The amendments are effective for fiscal years beginning after December 15, 2025. Early adoption is permitted. ASU 2024-02 is not expected to have a significant impact on the Corporation's financial statements. ASU 2024-03: The FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses The amendments in the ASU improve financial reporting by requiring that public business entities disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The amendments are effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. ASU 2024-03 is not expected to have a significant impact on the Corporation's financial statements. ASU 2024-04: The FASB issued ASU 2024-04, Debt—Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments The amendments in the ASU clarify the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion. The amendments in the ASU are effective for all entities for annual reporting periods beginning after December 15, 2025, and interim reporting periods within those annual reporting periods. Early adoption is permitted for all entities that have adopted the amendments in ASU 2020-06. ASU 2024-04 is not expected to have a significant impact on the Corporation's financial statements. ASU 2025-01 - The FASB issued ASU 2025-01, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date The amendments in the ASU clarify the effective date of ASU 2024-03 which requires public business entities to disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The amendments in the ASU are effective for the first annual reporting period beginning after December 15, 2026, and interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. ASU 2025-01 is not expected to have a significant impact on the Corporation's financial statements.

Mid Penn Bancorp, Inc. ("Mid Penn" or the "Corporation"), through operations conducted by Mid Penn Bank (the "Bank") and its nonbank subsidiaries, engages in a full-service commercial banking and trust business, making available to the community a wide range of financial services, including, but not limited to, mortgage and home equity loans, secured and unsecured commercial and consumer loans, lines of credit, construction financing, farm loans, community development loans, loans to non-profit entities and local government loans, and various types of time and demand deposits including but not limited to, checking accounts, savings accounts, clubs, money market deposit accounts, certificates of deposit, and Individual Retirement Accounts. In addition, the Bank provides a full range of trust and wealth management services through its Trust Department. Deposits are insured by the Federal Deposit Insurance Corporation ("FDIC") to the extent provided by law.

The financial services are provided to individuals, partnerships, non-profit organizations, and corporations through its retail banking offices located throughout Pennsylvania and three counties in New Jersey.

For all periods presented, the accompanying consolidated financial statements include the accounts of Mid Penn Bancorp, Inc., its wholly-owned subsidiary, Mid Penn Bank, and five wholly-owned nonbank subsidiaries, MPB Realty, LLC, MPB Financial Services, LLC, which includes MPB Wealth Management, LLC (which ceased operating during the first quarter

of 2024), MPB Risk Services, LLC, and MPB Launchpad Fund I, LLC. As of March 31, 2025, the accounts and activities of these nonbank subsidiaries were not material to warrant separate disclosure or segment reporting. As a result, Mid Penn has only one reportable segment for financial reporting purposes. All material intercompany accounts and transactions have been eliminated in consolidation.

Certain information and disclosures normally included in consolidated financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. Mid Penn believes the information presented is not misleading, and the disclosures are adequate. For comparative purposes, the March 31, 2024 and December 31, 2024 balances have been reclassified, when necessary, to conform to the 2025 presentation. Such reclassifications had no impact on net income or total shareholders’ equity. In the opinion of management, all adjustments necessary for fair presentation of the periods presented have been reflected in the accompanying consolidated financial statements. All such adjustments are of a normal, recurring nature. These unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the 2024 Annual Report.

Mid Penn has evaluated events and transactions occurring subsequent to the balance sheet date of March 31, 2025 for items that should potentially be recognized or disclosed in these consolidated financial statements. The evaluation was conducted through the issuance date of these consolidated financial statements.

On April 30, 2025, Mid Penn completed its acquisition of William Penn Bancorporation through the merger of William Penn with and into Mid Penn. The Merger was completed in accordance with the terms and conditions of the Agreement and Plan of Merger dated October 31, 2024, between Mid Penn and William Penn.

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could materially differ from those estimates.

Material estimates subject to significant change include the allowance for credit losses, the expected cash flows and collateral values associated with loans that are individually evaluated for credit losses, the carrying value of other real

estate owned ("OREO"), the fair value of financial instruments, business combination fair value computations, the valuation of goodwill and other intangible assets, stock-based compensation and deferred income tax assets.

ASU 2023-06 amends the ASC to incorporate certain disclosure requirements from SEC Release No. 33-10532 - Disclosure Update and Simplification that was issued in 2018. The effective date for each amendment will be the date on which the SEC’s removal of that related disclosure from Regulation S-X or Regulation S-K becomes effective, with early adoption prohibited. ASU 2023-06 is not expected to have a significant impact on the Corporation's financial statements.

ASU 2023-09 amends the ASC to enhance income tax disclosures by requiring entities to disclose income taxes paid (net of refunds received) disaggregated by federal, state and foreign taxes. Additionally, entities are required to disclose amounts greater than 5% of the total income taxes paid to an individual jurisdiction The amendments are effective for annual periods beginning after December 15, 2024. ASU 2023-09 is not expected to have a significant impact on the Corporation's financial statements.

The amendments in the ASU apply to all reporting entities that account for profits interest awards as compensation to employees or nonemployees in return for goods or services. The amendments are effective for annual periods beginning after December 15, 2025, and interim periods within those annual periods. ASU 2024-01 is not expected to have a significant impact on the Corporation's financial statements.

This ASU contains amendments to the Codification that remove references to various FASB Concepts Statements. The amendments are effective for fiscal years beginning after December 15, 2025. Early adoption is permitted. ASU 2024-02 is not expected to have a significant impact on the Corporation's financial statements.

The amendments in the ASU improve financial reporting by requiring that public business entities disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The amendments are effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. ASU 2024-03 is not expected to have a significant impact on the Corporation's financial statements.

The amendments in the ASU clarify the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion. The amendments in the ASU are effective for all entities for annual reporting periods beginning after December 15, 2025, and interim reporting periods within those annual reporting periods. Early adoption is permitted for all entities that have adopted the amendments in ASU 2020-06. ASU 2024-04 is not expected to have a significant impact on the Corporation's financial statements.

The amendments in the ASU clarify the effective date of ASU 2024-03 which requires public business entities to disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The amendments in the ASU are effective for the first annual reporting period beginning after December 15, 2026, and interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. ASU 2025-01 is not expected to have a significant impact on the Corporation's financial statements.