Recent Accounting Pronouncements	6 Months Ended
Jun. 30, 2018
New Accounting Pronouncement Or Change In Accounting Principle Retrospective Adjustments [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements ASU 2016-13: The FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The ASU requires credit losses on most financial assets measured at amortized cost and certain other instruments to be measured using an expected credit loss model (referred to as the current expected credit loss (“CECL”) model). Under this model, entities will estimate credit losses over the entire contractual term of the instrument (considering estimated prepayments, but not expected extensions or modifications unless reasonable expectation of a troubled debt restructuring exists) from the date of initial recognition of that instrument. The ASU also replaces the current accounting model for purchased credit impaired loans and debt securities. The allowance for purchased financial assets with a more-than insignificant amount of credit deterioration since origination (“PCD assets”) should be determined in a similar manner to other financial assets measured on an amortized cost basis. However, upon initial recognition, the allowance is added to the purchase price (“gross up approach”) to determine the initial amortized cost basis. The subsequent accounting for PCD financial assets is the same expected loss model described above. Further, the ASU made certain targeted amendments to the existing impairment model for available-for-sale debt securities. For an AFS debt security for which there is neither the intent nor a more-likely-than-not requirement to sell, an entity will record credit losses as an allowance rather than a write-down of the amortized cost basis. Certain incremental disclosures are required. The Update has tiered effective dates, with early adoption permitted for all entities as of the fiscal year beginning after December 15, 2018. For public business entities that are SEC filers, the amendments are effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. For all other public business entities, the amendments are effective for fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. For all other entities, including not-for-profit entities and employee benefit plans within the scope of Topics 960 through 965 on plan accounting, the amendments are effective for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. Mid Penn is currently evaluating the details of this ASU and the impact the guidance will have on Mid Penn’s consolidated financial statements. Mid Penn expects that it is possible that the ASU may result in an increase in the allowance for credit losses resulting from the change to expected losses for the estimated life of the financial asset, including an allowance for debt securities. The amount of the change in the allowance for credit losses, if any, resulting from the new guidance will be impacted by the portfolio composition and asset quality at the adoption date, as well as economic conditions and forecasts at the time of adoption. ASU 2016-02: The FASB issued ASU 2016-02, Leases. The new leases standard applies a right-of-use (“ROU”) model that requires a lessee to record, for all leases with a lease term of more than 12 months, an asset representing its right to use the underlying asset and a liability to make lease payments. For leases with a term of 12 months or less, a practical expedient is available whereby a lessee may elect, by class of underlying asset, not to recognize an ROU asset or lease liability. At inception, lessees must classify all leases as either finance or operating based on five criteria. Balance sheet recognition of finance and operating leases is similar, but the pattern of expense recognition in the income statement, as well as the effect on the statement of cash flows, differs depending on the lease classification. The new leases standard requires a lessor to classify leases as either sales-type, direct financing or operating, similar to existing U.S. GAAP. Classification depends on the same five criteria used by lessees plus certain additional factors. The subsequent accounting treatment for all three lease types is substantially equivalent to existing U.S. GAAP for sales-type leases, direct financing leases, and operating leases. However, the new standard updates certain aspects of the lessor accounting model to align it with the new lessee accounting model, as well as with the new revenue standard under Topic 606. Lessees and lessors are required to provide certain qualitative and quantitative disclosures to enable users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The new leases standard addresses other considerations including identification of a lease, separating lease and non-lease components of a contract, sale and leaseback transactions, modifications, combining contracts, reassessment of the lease term, and re-measurement of lease payments. It also contains comprehensive implementation guidance with practical examples. On July 30, 2018, the FASB issued ASU 2018-11, Leases (Topic 842): Targeted Improvements, which provides an option to apply the transition provisions of the new standard at the adoption date instead of the earliest comparative period presented. Additionally, the ASU provides a practical expedient permitting lessors to not separate non-lease components from the associated lease component if certain conditions are met. The amendments for both ASUs are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. Specific transition requirements apply. The amendments are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. Specific transition requirements apply. Mid Penn occupies certain offices under non-cancelable operating lease agreements, which currently are not reflected in its consolidated statement of condition. Mid Penn expects to recognize lease liabilities and ROU assets associated with these lease agreements as required by the ASU; however, the extent of the prospective impact on Mid Penn’s consolidated financial statements and the materiality will be dependent upon the extent and type of lease arrangements involving Mid Penn at the time of the adoption of this standard. ASU 2018-07: The FASB issued ASU 2018-07, Compensation – Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting The ASU makes certain changes to the accounting for nonemployee awards to alight the accounting for share-based payment awards issued to employees and nonemployees. The changes require that the compensation expense associated with nonemployee equity awards with performance conditions be recognized when the achievement of the performance condition is probable, rather than upon achievement of the performance condition. Additionally, the new ASU requires that equity-classified share-based payment awards issued to nonemployees be measured on the grant date, versus the previous GAAP requirement to re-measure the awards through the performance completion date. The current requirement to reassess the classification (equity or liability) for the nonemployee awards upon vesting will be eliminated. The amendments are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted, including interim periods. Mid Penn currently issues restricted stock awards to nonemployee directors through the 2014 Restricted Stock Plan (the “Plan”). The single performance condition of the award is that the individual remain a director of Mid Penn through the duration of the vesting period. Mid Penn is currently evaluating the details of this ASU and expects that the adoption of this ASU will not have a material impact on our consolidated financial statements as the compensation expense related to nonemployee equity awards is immaterial to Mid Penn’s overall financial condition.

Recent Accounting Pronouncements

ASU 2016-13: The FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.

The ASU requires credit losses on most financial assets measured at amortized cost and certain other instruments to be measured using an expected credit loss model (referred to as the current expected credit loss (“CECL”) model). Under this model, entities will estimate credit losses over the entire contractual term of the instrument (considering estimated prepayments, but not expected extensions or modifications unless reasonable expectation of a troubled debt restructuring exists) from the date of initial recognition of that instrument.

The ASU also replaces the current accounting model for purchased credit impaired loans and debt securities. The allowance for purchased financial assets with a more-than insignificant amount of credit deterioration since origination (“PCD assets”) should be determined in a similar manner to other financial assets measured on an amortized cost basis. However, upon initial recognition, the allowance is added to the purchase price (“gross up approach”) to determine the initial amortized cost basis. The subsequent accounting for PCD financial assets is the same expected loss model described above.

Further, the ASU made certain targeted amendments to the existing impairment model for available-for-sale debt securities. For an AFS debt security for which there is neither the intent nor a more-likely-than-not requirement to sell, an entity will record credit losses as an allowance rather than a write-down of the amortized cost basis. Certain incremental disclosures are required.

The Update has tiered effective dates, with early adoption permitted for all entities as of the fiscal year beginning after December 15, 2018. For public business entities that are SEC filers, the amendments are effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. For all other public business entities, the amendments are effective for fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. For all other entities, including not-for-profit entities and employee benefit plans within the scope of Topics 960 through 965 on plan accounting, the amendments are effective for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021.

Mid Penn is currently evaluating the details of this ASU and the impact the guidance will have on Mid Penn’s consolidated financial statements. Mid Penn expects that it is possible that the ASU may result in an increase in the allowance for credit losses resulting from the change to expected losses for the estimated life of the financial asset, including an allowance for debt securities. The amount of the change in the allowance for credit losses, if any, resulting from the new guidance will be impacted by the portfolio composition and asset quality at the adoption date, as well as economic conditions and forecasts at the time of adoption.

ASU 2016-02: The FASB issued ASU 2016-02, Leases.

The new leases standard applies a right-of-use (“ROU”) model that requires a lessee to record, for all leases with a lease term of more than 12 months, an asset representing its right to use the underlying asset and a liability to make lease payments. For leases with a term of 12 months or less, a practical expedient is available whereby a lessee may elect, by class of underlying asset, not to recognize an ROU asset or lease liability. At inception, lessees must classify all leases as either finance or operating based on five criteria. Balance sheet recognition of finance and operating leases is similar, but the pattern of expense recognition in the income statement, as well as the effect on the statement of cash flows, differs depending on the lease classification.

The new leases standard requires a lessor to classify leases as either sales-type, direct financing or operating, similar to existing U.S. GAAP. Classification depends on the same five criteria used by lessees plus certain additional factors. The subsequent accounting treatment for all three lease types is substantially equivalent to existing U.S. GAAP for sales-type leases, direct financing leases, and operating leases. However, the new standard updates certain aspects of the lessor accounting model to align it with the new lessee accounting model, as well as with the new revenue standard under Topic 606.

Lessees and lessors are required to provide certain qualitative and quantitative disclosures to enable users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The new leases standard addresses other considerations including identification of a lease, separating lease and non-lease components of a contract, sale and leaseback transactions, modifications, combining contracts, reassessment of the lease term, and re-measurement of lease payments. It also contains comprehensive implementation guidance with practical examples.

On July 30, 2018, the FASB issued ASU 2018-11, Leases (Topic 842): Targeted Improvements, which provides an option to apply the transition provisions of the new standard at the adoption date instead of the earliest comparative period presented. Additionally, the ASU provides a practical expedient permitting lessors to not separate non-lease components from the associated lease component if certain conditions are met.

The amendments for both ASUs are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. Specific transition requirements apply.

The amendments are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. Specific transition requirements apply.

Mid Penn occupies certain offices under non-cancelable operating lease agreements, which currently are not reflected in its consolidated statement of condition. Mid Penn expects to recognize lease liabilities and ROU assets associated with these lease agreements as required by the ASU; however, the extent of the prospective impact on Mid Penn’s consolidated financial statements and the materiality will be dependent upon the extent and type of lease arrangements involving Mid Penn at the time of the adoption of this standard.

ASU 2018-07: The FASB issued ASU 2018-07, Compensation – Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting

The ASU makes certain changes to the accounting for nonemployee awards to alight the accounting for share-based payment awards issued to employees and nonemployees. The changes require that the compensation expense associated with nonemployee equity awards with performance conditions be recognized when the achievement of the performance condition is probable, rather than upon achievement of the performance condition. Additionally, the new ASU requires that equity-classified share-based payment awards issued to nonemployees be measured on the grant date, versus the previous GAAP requirement to re-measure the awards through the performance completion date. The current requirement to reassess the classification (equity or liability) for the nonemployee awards upon vesting will be eliminated.

Mid Penn currently issues restricted stock awards to nonemployee directors through the 2014 Restricted Stock Plan (the “Plan”). The single performance condition of the award is that the individual remain a director of Mid Penn through the duration of the vesting period. Mid Penn is currently evaluating the details of this ASU and expects that the adoption of this ASU will not have a material impact on our consolidated financial statements as the compensation expense related to nonemployee equity awards is immaterial to Mid Penn’s overall financial condition.