v3.22.1

Commitments, Contingencies and Guarantees - Unfunded Commitments (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Gain Contingencies [Line Items] |  |
Fair Value | $ 67,278 | $ 68,262
% of Total | 100.00% | 100.00%
Private credit funds |  |
Gain Contingencies [Line Items] |  |
Fair Value | $ 3,771 | $ 4,897
% of Total | 5.60% | 7.20%
Investments in direct lending entities (at cost) |  |
Gain Contingencies [Line Items] |  |
Fair Value | $ 9,912 | $ 13,216
% of Total | 14.70% | 19.40%
Other privately held investments |  |
Gain Contingencies [Line Items] |  |
Fair Value | $ 1,900 | $ 4,000
% of Total | 2.80% | 5.80%
Private equity funds |  |
Gain Contingencies [Line Items] |  |
Fair Value | $ 51,695 | $ 46,149
% of Total | 76.90% | 67.60%

X
- Definition Fair Value, Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments, Percentage Of Total + References No definition available. + Details
Name: | mhld_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommitmentsPercentageOfTotal
Namespace Prefix: | mhld_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123874694&loc=SL6742756-110258 + Details
Name: | us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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_GainContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_InvestmentTypeAxis=mhld_PrivateCreditLendingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=mhld_DirectLendingEntitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=mhld_OtherPrivatelyHeldInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_PrivateEquityFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |