Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionGrantsInPeriod
Namespace Prefix:	mmab_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the non-employee compensation plan.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsExercisableNumber
Namespace Prefix:	mmab_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The weighted-average exercise price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the non-employee compensation plan.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsExercisableWeightedAverageExercisePrice
Namespace Prefix:	mmab_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsExercisableWeightedAverageRemainingContractualTerm
Namespace Prefix:	mmab_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Weighted average exercise price of options that were either forfeited or expired.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsExpiredWeightedAverageExercisePrice
Namespace Prefix:	mmab_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the non-employee directors stock based compensation plan or that expired.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsForfeituresAndExpirationsInPeriod
Namespace Prefix:	mmab_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Weighted average exercise price of options that were granted.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsGrantedWeightedAverageExercisePrice
Namespace Prefix:	mmab_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Weighted average remaining contractual term for option awards granted, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsGrantedWeightedAverageRemainingContractualTerm
Namespace Prefix:	mmab_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsOutstandingIntrinsicValue
Namespace Prefix:	mmab_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The number of shares reserved for issuance under non-employee directors Stock-based Compensation Plan that validly exist and are outstanding as of the balance sheet date, including vested options.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsOutstandingNumber
Namespace Prefix:	mmab_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The weighted average exercise price of shares reserved for issuance under non-employee directors stock-based compensation plan that validly exist and are outstanding as of the balance sheet date, including vested options.

No definition available.

Name:	mmab_ShareBasedGoodsAndNonemployeeServicesTransactionOptionsWeightedAverageExercisePrice
Namespace Prefix:	mmab_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.