Acquisition of Riverview Financial Corporation - Fair Value Adjustments (Details) - Riverview - USD ($) $ in Thousands	Nov. 30, 2021	Sep. 30, 2022
Business Acquisition [Line Items]
Gross amortized cost basis at November 30, 2021	$ 850,920
Market rate adjustment	529
Credit fair value adjustment on pools of homogeneous loans	(13,117)
Credit fair value adjustment on impaired loans	(827)
Loans	$ 837,505	$ 837,505

Purchased loans credit fair value adjustment on impaired loans

No definition available.

Name:	mpb_PurchasedLoansCreditFairValueAdjustmentOnImpairedLoans
Namespace Prefix:	mpb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Purchased loans, credit fair value adjustment on pools of homogeneous loans

+ References

No definition available.

+ Details

Name:	mpb_PurchasedLoansCreditFairValueAdjustmentOnPoolsOfHomogeneousLoans
Namespace Prefix:	mpb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Purchased loans market rate adjustment

+ References

No definition available.

+ Details

Name:	mpb_PurchasedLoansMarketRateAdjustment
Namespace Prefix:	mpb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

- Definition

Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=128092470&loc=d3e4845-128472

+ Details

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

- Definition

The amount of financial assets (as defined) recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-URI https://asc.fasb.org/topic&trid=2134543

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI https://asc.fasb.org/extlink&oid=123455525&loc=d3e2207-128464

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=128092470&loc=d3e4845-128472

+ Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=mpb_RiverviewMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: