Fair Value Measurement (Policy)	6 Months Ended
Jun. 30, 2016
Fair Value Measurement [Abstract]
Fair Value Measurement	The following methodologies and assumptions were used to estimate the fair value of Mid Penn’s financial instruments: Cash and Cash Equivalents: The carrying value of cash and cash equivalents is considered to be a reasonable estimate of fair value. Interest-bearing Balances with other Financial Institutions: The estimate of fair value was determined by comparing the present value of quoted interest rates on like deposits with the weighted average yield and weighted average maturity of the balances. Securities Available for Sale: The fair value of securities classified as available for sale is determined by obtaining quoted market prices on nationally recognized securities exchanges (Level 1), or matrix pricing (level 2), which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted market prices for the specific securities but rather relying on the securities’ relationship to other benchmark quoted prices. Impaired Loans (included in “Net Loans and Leases” in the following tables): Mid Penn’s rating system assumes any loans classified as substandard and nonaccrual to be impaired, and all of these loans are considered collateral dependent; therefore, all of Mid Penn’s impaired loans, whether reporting a specific allocation or not, are considered collateral dependent. It is Mid Penn’s policy to obtain updated third party valuations on all impaired loans collateralized by real estate within 30 days of the credit being classified as substandard nonaccrual. Prior to receipt of the updated real estate valuation Mid Penn will use any existing real estate valuation to determine any potential allowance issues; however no allowance recommendation will be made until which time Mid Penn is in receipt of the updated valuation. In some instances Mid Penn is not holding real estate as collateral and is relying on business assets (personal property) for repayment. In these circumstances a collateral inspection is performed by Mid Penn personnel to determine an estimated value. The value is based on net book value, as provided by the financial statements, and discounted accordingly based on determinations made by management. Occasionally, Mid Penn will employ an outside service to provide a fair estimate of value based on auction sales or private sales. Management reviews the estimates of these third parties and discounts them accordingly based on management’s judgment, if deemed necessary. Mid Penn considers the estimates used in its impairment analysis to be Level 3 inputs. Mid Penn actively monitors the values of collateral on impaired loans. This monitoring may require the modification of collateral values over time or changing circumstances by some factor, either positive or negative, from the original values. All collateral values will be assessed by management at least every 12 months for possible revaluation by an independent third party. Loans: For variable rate loans that reprice frequently and which entail no significant changes in credit risk, carrying values approximated fair value. The fair value of other loans are estimated by calculating the present value of the cash flow difference between the current rate and the market rate, for the average maturity, discounted quarterly at the market rate. Foreclosed Assets Held for Sale: Certain assets included in foreclosed assets held for sale are carried at fair value and accordingly is presented as measured on a non-recurring basis. Values are estimated using Level 3 inputs, based on appraisals that consider the sales prices of property in the proximate vicinity. Accrued Interest Receivable and Payable: The carrying amount of accrued interest receivable and payable approximates their fair values. Restricted Investment in Bank Stocks: The carrying amount of required and restricted investment in correspondent bank stock approximates fair value, and considers the limited marketability of such securities. Mortgage Servicing Rights: The fair value of servicing rights is based on the present value of estimated future cash flows on pools of mortgages stratified by rate and maturity date. Deposits: The fair value for demand deposits (e.g., interest and noninterest checking, savings, and money market deposit accounts) is by definition, equal to the amount payable on demand at the reporting date (i.e. their carrying amounts). Fair value for fixed-rate certificates of deposit was estimated using a discounted cash flow calculation by combining all fixed-rate certificates into a pool with a weighted average yield and a weighted average maturity for the pool and comparing the pool with interest rates currently being offered on a similar maturity. Short-term Borrowings: Because of time to maturity, the estimated fair value of short-term borrowings approximates the book value. Long-term and Subordinated Debt: The estimated fair values of long-term and subordinated debt were determined using discounted cash flow analysis, based on currently available borrowing rates for similar types of borrowing arrangements. Commitments to Extend Credit and Letters of Credit: The fair value of commitments to extend credit is estimated using the fees currently charged to enter into similar agreements, taking into account market interest rates, the remaining terms and present credit worthiness of the counterparties. The fair value of guarantees and letters of credit is based on fees currently charged for similar agreements.

The following methodologies and assumptions were used to estimate the fair value of Mid Penn’s financial instruments:

Cash and Cash Equivalents:

The carrying value of cash and cash equivalents is considered to be a reasonable estimate of fair value.

Interest-bearing Balances with other Financial Institutions:

The estimate of fair value was determined by comparing the present value of quoted interest rates on like deposits with the weighted average yield and weighted average maturity of the balances.

Securities Available for Sale:

The fair value of securities classified as available for sale is determined by obtaining quoted market prices on nationally recognized securities exchanges (Level 1), or matrix pricing (level 2), which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted market prices for the specific securities but rather relying on the securities’ relationship to other benchmark quoted prices.

Impaired Loans (included in “Net Loans and Leases” in the following tables):

Mid Penn’s rating system assumes any loans classified as substandard and nonaccrual to be impaired, and all of these loans are considered collateral dependent; therefore, all of Mid Penn’s impaired loans, whether reporting a specific allocation or not, are considered collateral dependent.

It is Mid Penn’s policy to obtain updated third party valuations on all impaired loans collateralized by real estate within 30 days of the credit being classified as substandard nonaccrual. Prior to receipt of the updated real estate valuation Mid Penn will use any existing real estate valuation to determine any potential allowance issues; however no allowance recommendation will be made until which time Mid Penn is in receipt of the updated valuation.

In some instances Mid Penn is not holding real estate as collateral and is relying on business assets (personal property) for repayment. In these circumstances a collateral inspection is performed by Mid Penn personnel to determine an estimated value. The value is based on net book value, as provided by the financial statements, and discounted accordingly based on determinations made by management. Occasionally, Mid Penn will employ an outside service to provide a fair estimate of value based on auction sales or private sales. Management reviews the estimates of these third parties and discounts them accordingly based on management’s judgment, if deemed necessary. Mid Penn considers the estimates used in its impairment analysis to be Level 3 inputs.

Mid Penn actively monitors the values of collateral on impaired loans. This monitoring may require the modification of collateral values over time or changing circumstances by some factor, either positive or negative, from the original values. All collateral values will be assessed by management at least every 12 months for possible revaluation by an independent third party.

Loans:

For variable rate loans that reprice frequently and which entail no significant changes in credit risk, carrying values approximated fair value. The fair value of other loans are estimated by calculating the present value of the cash flow difference between the current rate and the market rate, for the average maturity, discounted quarterly at the market rate.

Foreclosed Assets Held for Sale:

Certain assets included in foreclosed assets held for sale are carried at fair value and accordingly is presented as measured on a non-recurring basis. Values are estimated using Level 3 inputs, based on appraisals that consider the sales prices of property in the proximate vicinity.

Accrued Interest Receivable and Payable:

The carrying amount of accrued interest receivable and payable approximates their fair values.

Restricted Investment in Bank Stocks:

The carrying amount of required and restricted investment in correspondent bank stock approximates fair value, and considers the limited marketability of such securities.

Mortgage Servicing Rights:

The fair value of servicing rights is based on the present value of estimated future cash flows on pools of mortgages stratified by rate and maturity date.

Deposits:

The fair value for demand deposits (e.g., interest and noninterest checking, savings, and money market deposit accounts) is by definition, equal to the amount payable on demand at the reporting date (i.e. their carrying amounts). Fair value for fixed-rate certificates of deposit was estimated using a discounted cash flow calculation by combining all fixed-rate certificates into a pool with a weighted average yield and a weighted average maturity for the pool and comparing the pool with interest rates currently being offered on a similar maturity.

Short-term Borrowings:

Because of time to maturity, the estimated fair value of short-term borrowings approximates the book value.

Long-term and Subordinated Debt:

The estimated fair values of long-term and subordinated debt were determined using discounted cash flow analysis, based on currently available borrowing rates for similar types of borrowing arrangements.

Commitments to Extend Credit and Letters of Credit:

The fair value of commitments to extend credit is estimated using the fees currently charged to enter into similar agreements, taking into account market interest rates, the remaining terms and present credit worthiness of the counterparties. The fair value of guarantees and letters of credit is based on fees currently charged for similar agreements.