Loans and Allowance for Loan and Lease Losses (Allowance And Recorded Investment In Financing Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	$ 13,382	$ 9,515
Charge-offs	(865)	(58)
Recoveries	74	7
Provisions (credits)	1,000	550
Allowance for Loan Losses, Ending balance	13,591	10,014
Allowance for loan losses: Ending balance: individually evaluated for impairment	331	193	$ 807
Allowance for loan losses: Ending balance: collectively evaluated for impairment	13,260	9,821	12,575
Loans receivables, Ending balance	2,646,236	1,798,149	2,384,041
Loans receivables: Ending balance: individually evaluated for impairment	4,959	9,357	13,768
Loans Receivable: Ending balance: collectively evaluated for impairment	2,639,560	1,787,000	2,368,531
Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivables, Ending balance	1,717	1,792	1,742
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	507	442
Provisions (credits)	21	6
Allowance for Loan Losses, Ending balance	528	448
Allowance for loan losses: Ending balance: collectively evaluated for impairment	528	448	507
Loans receivables, Ending balance	75,423	64,610	74,224
Loans receivables: Ending balance: individually evaluated for impairment	2,334	24	2,365
Loans Receivable: Ending balance: collectively evaluated for impairment	73,089	64,585	71,859
Home Equity [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivables, Ending balance		1
Commercial Portfolio [Member] \| Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	3,066	2,341
Charge-offs	(859)	(43)
Recoveries	1	1
Provisions (credits)	780	128
Allowance for Loan Losses, Ending balance	2,988	2,427
Allowance for loan losses: Ending balance: individually evaluated for impairment	68	3	533
Allowance for loan losses: Ending balance: collectively evaluated for impairment	2,920	2,424	2,533
Loans receivables, Ending balance	964,045	351,339	752,354
Loans receivables: Ending balance: individually evaluated for impairment	368	897	1,452
Loans Receivable: Ending balance: collectively evaluated for impairment	963,677	350,442	750,902
Commercial Portfolio [Member] \| Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	8,655	6,259
Recoveries	56	1
Provisions (credits)	233	370
Allowance for Loan Losses, Ending balance	8,944	6,630
Allowance for loan losses: Ending balance: individually evaluated for impairment	263	190	274
Allowance for loan losses: Ending balance: collectively evaluated for impairment	8,681	6,440	8,381
Loans receivables, Ending balance	1,135,660	939,995	1,099,656
Loans receivables: Ending balance: individually evaluated for impairment	1,469	7,649	9,102
Loans Receivable: Ending balance: collectively evaluated for impairment	1,132,783	930,923	1,089,135
Commercial Portfolio [Member] \| Commercial Real Estate [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivables, Ending balance	1,408	1,423	1,419
Commercial Portfolio [Member] \| Commercial Real Estate - Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	134	51
Provisions (credits)	(12)	6
Allowance for Loan Losses, Ending balance	122	57
Allowance for loan losses: Ending balance: collectively evaluated for impairment	122	57	134
Loans receivables, Ending balance	264,945	205,248	248,913
Loans receivables: Ending balance: individually evaluated for impairment	30	39	31
Loans Receivable: Ending balance: collectively evaluated for impairment	264,915	205,209	248,882
Residential Portfolio [Member] \| Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	429	417
Charge-offs	(3)
Recoveries	9	3
Provisions (credits)	3	16
Allowance for Loan Losses, Ending balance	438	436
Allowance for loan losses: Ending balance: collectively evaluated for impairment	438	436	429
Loans receivables, Ending balance	197,788	230,047	201,841
Loans receivables: Ending balance: individually evaluated for impairment	758	748	818
Loans Receivable: Ending balance: collectively evaluated for impairment	196,721	228,931	200,700
Residential Portfolio [Member] \| Financial Asset Acquired with Credit Deterioration [Member] \| Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivables, Ending balance	309	368	323
Consumer Portfolio [Member] \| Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	1	2
Charge-offs	(3)	(15)
Recoveries	8	2
Provisions (credits)	(5)	13
Allowance for Loan Losses, Ending balance	1	2
Allowance for loan losses: Ending balance: collectively evaluated for impairment	1	2	1
Loans receivables, Ending balance	8,375	6,910	7,053
Loans Receivable: Ending balance: collectively evaluated for impairment	8,375	6,910	7,053
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning balance	590	3
Provisions (credits)	(20)	11
Allowance for Loan Losses, Ending balance	570	14
Allowance for loan losses: Ending balance: collectively evaluated for impairment	$ 570	$ 14	$ 590

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(2))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

+ Details

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

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

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

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix:	us-gaap_
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_FinancingReceivableAllowanceForCreditLossesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922352-210448

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
-Paragraph 79
-URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922352-210448

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

+ Details

Name:	us-gaap_LoansAndLeasesReceivableGrossCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

+ Details

Name:	us-gaap_ProvisionForLoanAndLeaseLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CreditLossStatusAxis=us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mpb_CommercialAndIndustrialLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_RealEstateLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ConsumerLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_UnallocatedFinancingReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: