v2.4.0.8

Investments - Restricted Cash and Investments (Details) (USD $) In Thousands, unless otherwise specified | Jun. 30, 2013 | Dec. 31, 2012
--- | --- | ---
Restricted Cash and Investments Items [Line Items] |  |
Restricted cash | $ 96,215 | $ 132,327
Restricted investments | 2,060,755 | 2,034,991
Restricted cash and investments | 2,156,970 | 2,167,318
Amortized cost | 2,669,957 | 2,477,801
Third party agreements [Member] |  |
Restricted Cash and Investments Items [Line Items] |  |
Restricted cash | 87,723 | 97,695
Restricted investments | 989,954 | 1,101,971
Amortized cost | 969,747 | 1,048,827
Related party agreements [Member] |  |
Restricted Cash and Investments Items [Line Items] |  |
Restricted cash | 7,647 | 33,882
Restricted investments | 1,057,570 | 919,557
Amortized cost | 1,027,277 | 851,873
US state regulatory authorities [Member] |  |
Restricted Cash and Investments Items [Line Items] |  |
Restricted cash | 845 | 750
Restricted investments | 13,231 | 13,463
Amortized cost | $ 12,737 | $ 12,744

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- Definition Investments, Original or Amortized Cost Basis + References No definition available. + Details
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Namespace Prefix: | mhld_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Details
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Namespace Prefix: | mhld_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 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 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet. + References No definition available. + Details
Name: | us-gaap_RestrictedCashAndInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet. + References No definition available. + Details
Name: | us-gaap_RestrictedInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant