Debt (Long-term Debt Outstanding by Due Date) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Less: fair value adjustments on debt assumed in acquisitions		$ (41)
Total FHLB fixed rate instruments	$ 81,773	29,352
Lease obligations included in long-term debt	3,509	3,551
Total long-term debt	$ 85,282	32,903
Due in June 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 2,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	1.72%	1.72%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-06	2020-06
Due in July 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 5,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	2.45%	2.45%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-07	2020-07
Due in August 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding	$ 5,000	$ 5,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	3.05%	3.05%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-08	2020-08
Due in September 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 2,500
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	2.38%	2.38%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-09	2020-09
Due in October 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding	$ 5,000	$ 5,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	3.06%	3.06%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-10	2020-10
Due in November 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 3,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	2.32%	2.32%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-11	2020-11
Due in December 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 2,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	1.78%	1.78%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-12	2020-12
Due in December 2020 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 3,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	2.31%	2.31%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2020-12	2020-12
Due in April 2022 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding	$ 70,000
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	0.86%	0.86%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2022-04	2022-04
Due in August 2026 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding	$ 1,728	$ 1,846
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	4.80%	4.80%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2026-08	2026-08
Due in February 2027 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding	$ 45	$ 47
Federal Home Loan Bank, advances, branch of FHLB bank, interest rate	6.71%	6.71%
Federal Home Loan Bank, advances, branch of FHLB bank, due date	2027-02	2027-02

Fair value adjustment on debt assumed in acquisitions.

No definition available.

Name:	mpb_FairValueAdjustmentOnDebtAssumedInAcquisitions
Namespace Prefix:	mpb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Federal home loan bank advances branch of FHLB bank due date year month.

+ References

No definition available.

+ Details

Name:	mpb_FederalHomeLoanBankAdvancesBranchOfFHLBBankDueDateYearMonth
Namespace Prefix:	mpb_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Federal home loan bank advances lease obligations included in long term debt.

+ References

No definition available.

+ Details

Name:	mpb_FederalHomeLoanBankAdvancesLeaseObligationsIncludedInLongTermDebt
Namespace Prefix:	mpb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Federal home loan bank advances long term after fair value adjustment..

+ References

No definition available.

+ Details

Name:	mpb_FederalHomeLoanBankAdvancesLongTermAfterFairValueAdjustment
Namespace Prefix:	mpb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Federal Home Loan Bank advances long-term before fair value adjustment.

+ References

No definition available.

+ Details

Name:	mpb_FederalHomeLoanBankAdvancesLongTermBeforeFairValueAdjustment
Namespace Prefix:	mpb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesBranchOfFHLBBankInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64702-112823

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesLongTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=mpb_DebtInstrumentRedemptionPeriodSixMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=mpb_DebtInstrumentRedemptionPeriodSevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=mpb_DebtInstrumentRedemptionPeriodEightMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=mpb_DebtInstrumentRedemptionPeriodNineMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=mpb_DebtInstrumentRedemptionPeriodTenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=mpb_DebtInstrumentRedemptionPeriodElevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: