Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyAmortizedCostAbstract
Namespace Prefix:	mmac_
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The amortized cost of bonds prepayable without restriction or penalty for the current period.

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyAmortizedCostCurrent
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amortized cost of bonds prepayable without restriction or penalty within the third fiscal year following the latest fiscal year.

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyAmortizedCostYearThree
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amortized cost of bonds prepayable without restriction or penalty within the second fiscal year following the latest fiscal year.

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyAmortizedCostYearTwo
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyFairValueAbstract
Namespace Prefix:	mmac_
Data Type:	xbrli:stringItemType
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The fair value of bonds prepayable without restriction or penalty for the current period.

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyFairValueCurrent
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The fair value of bonds prepayable without restriction or penalty within the third fiscal year following the latest fiscal year.

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyFairValueYearThree
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The fair value of bonds prepayable without restriction or penalty within the second fiscal year following the latest fiscal year.

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyFairValueYearTwo
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Bonds, Prepayable Without Restriction Or Penalty, Unpaid Principal Balance, Current

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyUnpaidPrincipalBalanceCurrent
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Bonds, Prepayable Without Restriction Or Penalty, Unpaid Principal Balance, Year Three

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyUnpaidPrincipalBalanceYearThree
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Bonds, Prepayable Without Restriction Or Penalty, Unpaid Principal Balance, Year Two

No definition available.

Name:	mmac_BondsPrepayableWithoutRestrictionOrPenaltyUnpaidPrincipalBalanceYearTwo
Namespace Prefix:	mmac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Bonds Unpaid Principal Balance [Abstract].

No definition available.

Name:	mmac_BondsUnpaidPrincipalBalanceAbstract
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Data Type:	xbrli:stringItemType
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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
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Amount of debt securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
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