Name:	mpic_ImpairedFinancingReceivableAverageRecordedInvestment1
Namespace Prefix:	mpic_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of allowance for credit losses excluding accrued interest related to recorded investment.

No definition available.

Name:	mpic_ImpairedFinancingReceivableExcludingAccruedInterest
Namespace Prefix:	mpic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of investment in impaired financing receivables excluding accrued interest for which there is a related allowance for credit losses.

No definition available.

Name:	mpic_ImpairedFinancingReceivableExcludingAccruedInterestWithRelatedAllowanceRecordedInvestment
Namespace Prefix:	mpic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Unpaid principal balance of impaired financing receivables excluding accrued interest for which there is a related allowance for credit losses.

No definition available.

Name:	mpic_ImpairedFinancingReceivableExcludingAccruedInterestWithRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix:	mpic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of investment in impaired financing receivables excluding accrued interest for which there is no related allowance for credit losses.

No definition available.

Name:	mpic_ImpairedFinancingReceivableExcludingAccruedWithNoRelatedAllowanceRecordedInvestment
Namespace Prefix:	mpic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of accrued interest on financing receivable modified during period for debtor experiencing financial difficulty.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-41

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

- References

No definition available.

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

- References

No definition available.

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

- References

No definition available.