2.2.0.25falsefalse02010 - Disclosure - Significant Accounting Policies (Policies)truefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $FROM_Jan01_2010_TO_Dec31_2010http://www.sec.gov/CIK0000911421duration2010-01-01T00:00:002010-12-31T00:00:00SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0EPSDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0pre_DisclosureSignificantAccountingPoliciesAbstractprefalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseDisclosure - Significant Accounting Policies [Abstract]3false0us-gaap_BasisOfAccountingus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The Company’s Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States (U.S. GAAP). The Consolidated Financial Statements include the accounts of the Company and its subsidiaries. Intercompany accounts and transactions have been eliminated. To facilitate comparison of information across periods, certain reclassifications have been made to prior year amounts to conform to the current year’s presentation. The Company’s Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States (U.S.falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescription of the basis of accounting used to prepare the financial statements (for example, U.S. Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).No authoritative reference available.falsefalseBasis of accounting4false0us-gaap_UseOfEstimatesus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The preparation of financial statements in conformity with U.S. GAAP requires Management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. While Management believes that the amounts included in the Consolidated Financial Statements reflect its best estimates and assumptions, actual results could differ from those estimates. The Company’s principal estimates include: •        Unpaid losses and loss expenses; •        Policy benefits for life and annuity contracts; •         Gross and net premiums written and net premiums earned; •        Recoverability of deferred acquisition costs; •        Recoverability of deferred tax assets; •        Valuation of goodwill and intangible assets; and •         Valuation of certain assets and derivative financial instruments that are measured using significant unobservable inputs. The preparation of financial statements in conformity with U.S. GAAP requires Management to make estimates and assumptions that affect the reported amounts offalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringProvides an entity's explanation that the preparation of financial statements in conformity with generally accepted accounting principles requires the use of management estimates. Estimates used in the determination of carrying amounts of assets or liabilities, or in disclosure of gain or loss contingencies should be disclosed if known information available prior to issuance of the financial statements indicates that both of these criteria are met: (1) It is at least reasonably possible that the estimate of the effect on the financial statements of a condition, situation, or set of circumstances that existed at the date of the financial statements will change in the near term (less than one year from the date of issuance) due to one or more future confirming events, and (2) The effect of the change would be material to the financial statements. The disclosure should indicate the nature of the uncertainty and include an indication that it is at least reasonably possible that a change in the estimate will occur in the near term. Disclosure of the factors that cause the estimate to be sensitive to change also is encouraged. Entities also may identify those areas that are subject to significant estimates.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-6 -Paragraph 11, 14 falsefalseUse Of Estimates5false0us-gaap_InsurancePremiumsRevenueRecognitionPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Gross premiums written and earned are based upon reports received from ceding companies, supplemented by the Company’s own estimates of premiums written and earned for which ceding company reports have not been received. Differences between such estimates and actual amounts are recorded in the period in which the estimates are changed or the actual amounts are determined. Net premiums written and earned are presented net of ceded premiums, which represent the cost of retrocessional protection purchased by the Company. Premiums are earned on a basis that is consistent with the risks covered under the terms of the reinsurance contracts, which is generally one to two years. For U.S. and European wind and certain other risks, premiums are earned commensurate with the seasonality of the underlying exposure. Unearned premiums represent the portion of premiums written which is applicable to the unexpired risks under contracts in force. Premiums related to individual life and annuity business are recorded over the premium-paying period on the underlying policies. Premiums on annuity and universal life contracts for which there is no significant mortality or critical illness risk are accounted for in a manner consistent with accounting for interest-bearing financial instruments and are not reported as revenues, but rather as direct deposits to the contract. Amounts assessed against annuity and universal life policyholders are recognized as revenue in the period assessed. Gross premiums written and earned are based upon reports received from ceding companies, supplemented by the Company’s own estimates of premiums writtenfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes an insurance entity's accounting policy for premium revenue recognition, including the basis for measurement and the timing of recognition of revenue from insurance premiums received from contract holders.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 13, 14, 15, 16 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 97 -Paragraph 15-22 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 22 -Paragraph 12, 13 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-LHI -Chapter 7 -Paragraph 12, 13, 18, 20 -IssueDate 2006-05-01 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-PLI -Chapter 3 -Paragraph 31, 32, 33 -IssueDate 2006-09-01 falsefalsePremiums6false0us-gaap_UnpaidPolicyClaimsAndClaimsAdjustmentExpensePolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The liability for unpaid losses and loss expenses includes amounts determined from loss reports on individual treaties (case reserves), additional case reserves when the Company’s loss estimate is higher than reported by the cedants (ACRs) and amounts for losses incurred but not yet reported to the Company (IBNR). Such reserves are estimated by Management based upon reports received from ceding companies, supplemented by the Company’s own actuarial estimates of reserves for which ceding company reports have not been received, and based on the Company’s own historical experience. To the extent that the Company’s own historical experience is inadequate for estimating reserves, such estimates may be determined based upon industry experience and Management’s judgment. The estimates are continually reviewed and the ultimate liability may be in excess of, or less than, the amounts provided. Any adjustments are reflected in the periods in which they are determined, which may affect the Company’s operating results in future periods. The liability for unpaid losses and loss expenses includes amounts determined from loss reports on individual treaties (case reserves), additional casefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAccounting policy describing an insurance entity's bases and methodologies for estimating the ultimate cost of settling insurance claims relating to insured events that have occurred on or before a particular date (ordinarily, the statement of financial position date). The estimated liability includes the amount of money that will be required for future payments of (a) claims that have been reported to the insurer, (b) claims related to insured events that have occurred but that have not been reported to the insurer as of the date the liability is estimated, and (c) claim adjustment expenses. Claims adjustment expenses include costs incurred in the claim settlement process such as legal fees; outside adjuster fees; and costs to record, process, and adjust claims.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph b -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-PLI -Chapter 4 -Paragraph 2, 34, 132, 133 -IssueDate 2006-09-01 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-5 -Paragraph 10 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 60 -Subparagraph a, b falsefalseLosses and Loss Expenses7false0us-gaap_FuturePolicyBenefitsLiabilityPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The liabilities for policy benefits for ordinary life and accident and health policies have been established based upon information reported by ceding companies, supplemented by the Company’s actuarial estimates of mortality, critical illness, persistency and future investment income, with appropriate provision to reflect uncertainty. Future policy benefit reserves for annuity and universal life contracts are carried at their accumulated values. Reserves for policy claims and benefits include both mortality and critical illness claims in the process of settlement, and claims that have been incurred but not yet reported. The liabilities for policy benefits for ordinary life and accident and health policies have been established based upon information reported by cedingfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAccounting policy pertaining to an insurance entity's net liability for future benefits (for example, death, cash surrender value) to be paid to or on behalf of policyholders, describing the bases, methodologies and components of the reserve, and assumptions regarding estimates of expected investment yields, mortality, morbidity, terminations and expenses.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph b -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-LHI -Chapter 7 -Section Appendix C -Paragraph C-13 -IssueDate 2006-05-01 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-PLI -Chapter 4 -Paragraph 2, 34, 132, 133 -IssueDate 2006-09-01 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-5 -Paragraph 10 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 60 -Subparagraph a, b falsefalseLife Policy Benefits8false0us-gaap_ReinsuranceAccountingPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The Company purchases retrocessional contracts to reduce its exposure to risk of losses on reinsurance assumed. Reinsurance recoverable on paid and unpaid losses involves actuarial estimates consistent with those used to establish the associated liabilities for unpaid losses and loss expenses and life policy benefits. The Company purchases retrocessional contracts to reduce its exposure to risk of losses on reinsurance assumed. Reinsurance recoverable on paid and unpaidfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescription of the nature, purpose and effect of ceded reinsurance transactions on the financial statements, and description of the methodologies and assumptions underlying determination of reinsurance recoverables and reinsurance payables. Should also separately disclose assumptions pertaining to foreign-based reinsurance, if applicable, and the nature and effect of material nonrecurring reinsurance transactions. May also state that the ceding insurer is not relieved of its primary obligation to policyholders.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph c -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 113 -Paragraph 27, 120 falsefalseReinsurance Accounting Policy9false0us-gaap_CapitalizationOfDeferredPolicyAcquisitionCostsPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Acquisition costs, primarily brokerage fees, commissions and excise taxes, which vary directly with, and are related to, the acquisition of reinsurance contracts, are capitalized and charged to expense as the related premium is earned. Anticipated losses and loss expenses, other costs and investment income related to these premiums are considered in determining the recoverability of deferred acquisition costs. Acquisition costs related to individual life and annuity contracts are deferred and amortized over the premium-paying periods in proportion to anticipated premium income, allowing for lapses, terminations and anticipated investment income. Acquisition costs related to universal life and single premium annuity contracts for which there is no significant mortality or critical illness risk are deferred and amortized over the lives of the contracts as a percentage of the estimated gross profits expected to be realized on the contracts. Acquisition costs, primarily brokerage fees, commissions and excise taxes, which vary directly with, and are related to, the acquisition of reinsurancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes an insurance entity's accounting policy for deferred policy acquisition costs, including the nature and amount of capitalized costs incurred to write or acquire insurance contracts, and the basis for and methodologies applied in capitalizing and amortizing such costs.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 60 -Subparagraph c falsefalseDeferred Acquisition Costs10false0pre_FundsHeldByReinsuredCompaniesPolicyTextBlockprefalsenadurationDescribes the accounting policies used to account for funds held by reinsured companies, including recognition of investment...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The Company writes certain business on a funds held basis. Under such contractual arrangements, the cedant retains the premiums that would have otherwise been paid to the Company and the Company earns interest on these funds. With the exception of those arrangements discussed below, the Company generally earns investment income on the funds held balances based upon a predetermined interest rate, either fixed contractually at the inception of the contract or based upon a recognized index (e.g., LIBOR). In certain circumstances, the Company may receive an investment return based upon either the result of a pool of assets held by the cedant, generally used to collateralize the funds held balance, or the investment return earned by the cedant on its entire investment portfolio. This is most common in the Company’s life reinsurance business. In these arrangements, gross investment returns are typically reflected in net investment income with a corresponding increase or decrease (net of a spread) being recorded as life policy benefits in the Company’s Consolidated Statements of Operations. In these arrangements, the Company is exposed, to a limited extent, to the underlying credit risk of the pool of assets inasmuch as the underlying life policies may have guaranteed minimum returns. In such cases, an embedded derivative exists and its fair value is recorded by the Company as an increase or decrease to the funds held balance. The Company writes certain business on a funds held basis. Under such contractual arrangements, the cedant retains the premiums that would have otherwise beenfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes the accounting policies used to account for funds held by reinsured companies, including recognition of investment income related to funds held.No authoritative reference available.falsefalseFunds Held by Reinsured Companies (Cedants)11false0pre_FundsHeldDirectlyManagedPolicyTextBlockprefalsenadurationThis item describes the accounting policies related to the segregated investment portfolio underlying the funds held -...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The Company elected the fair value option as of the Acquisition Date for substantially all of the fixed maturities, short-term investments and certain other invested assets in the segregated investment portfolio underlying the funds held – directly managed account, and accordingly, all changes in the fair value of the segregated investment portfolio underlying the funds held – directly managed account subsequent to the Acquisition Date are recorded in net realized and unrealized investment gains and losses in the Consolidated Statements of Operations. The Company elected the fair value option as of the Acquisition Date for substantially all of the fixed maturities, short-term investments and certain otherfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item describes the accounting policies related to the segregated investment portfolio underlying the funds held - directly managed account and related realized and unrealized gains and losses.No authoritative reference available.falsefalseFunds Held - Directly Managed12false0us-gaap_DepositContractsPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00In the normal course of its operations, the Company enters into certain contracts that do not meet the risk transfer provisions of U.S. GAAP. While these contracts do not meet risk transfer provisions for accounting purposes, there is a remote possibility that the Company will suffer a loss. The Company accounts for these contracts using the deposit accounting method, originally recording deposit liabilities for an amount equivalent to the consideration received. The consideration to be retained by the Company, irrespective of the experience of the contracts, is earned over the expected settlement period of the contracts, with any unearned portion recorded as a component of deposit liabilities. Actuarial studies are used to estimate the final liabilities under these contracts and the appropriate accretion rates to increase or decrease the liabilities over the term of the contracts. The change for the period is recorded in other income or loss in the Consolidated Statements of Operations. Under some of these contracts, cedants retain the assets on a funds-held basis. In those cases, the Company records those assets as deposit assets and records the related income in net investment income in the Consolidated Statements of Operations. In the normal course of its operations, the Company enters into certain contracts that do not meet the risk transfer provisions of U.S. GAAP. While thesefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes an insurance entity's accounting policies pertaining to the treatment of funds received from or paid to insureds, insurers and reinsurers on contracts for which the criteria for transferring or assuming insurance risk has not been satisfied by the insurer or reinsurer.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 113 -Paragraph 18 falsefalseDeposit Assets and Liabilities13false0us-gaap_InvestmentPolicyTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Effective January 1, 2008, the Company elected the fair value option for all of its fixed maturities, short-term investments, equities and certain other invested assets (excluding those that are accounted for using the cost or equity methods of accounting or investment company accounting). The Company defines fair value as the price received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The Company measures the fair value of financial instruments according to a fair value hierarchy that prioritizes the information used to measure fair value into three broad levels. Following the election of the fair value option for an eligible item, changes in that item's fair value in subsequent reporting periods must be recognized in earnings. See Note 3 for additional information on fair value. The election of the fair value option resulted in a cumulative effect adjustment of $106.0 million, net of taxes, which decreased accumulated other comprehensive income and increased opening retained earnings as of January 1, 2008. There was no impact on the Company's consolidated net income, shareholders' equity or its comprehensive income.The Company elected the fair value option as of the Acquisition Date for all of Paris Re's fixed maturities and short-term investments and certain other invested assets.Short-term investments comprise securities with a maturity greater than three months but less than one year from the date of purchase. Other invested assets consist primarily of investments in non-publicly traded companies, private placement equity and fixed maturity investments, derivative financial instruments and other specialty asset classes. Entities in which the Company has an ownership of more than 20% and less than 50% of the voting shares, and limited partnerships in which the Company has more than a minor interest, are accounted for using the equity method. Other invested assets are recorded based on valuation techniques depending on the nature of the individual assets. The valuation techniques used by the Company are generally commensurate with standard valuation techniques for each asset class. Net investment income includes interest and dividend income, amortization of premiums and discounts on fixed maturities and short-term investments and investment income on funds held and funds held – directly managed, and is net of investment expenses and withholding taxes. Investment income is recognized when earned. Realized gains and losses on the disposal of investments are determined on a first-in, first-out basis. Investment purchases and sales are recorded on a trade-date basis.  Effective January 1, 2008, the Company elected the fair value option for all of its fixed maturities, short-term investments, equities and certain otherfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes an entity's accounting policies for investments in financial assets, including marketable securities (debt and equity securities with readily determinable fair values), investments accounted for under the equity method and cost method, securities borrowed and loaned, and repurchase and resale agreements. For marketable securities, the description may include the entity's accounting treatment for transfers between investment categories and how the fair values for such securities are determined. Also, for all investments, an entity may describe its policy for assessing, recognizing and measuring impairment of the investment.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 7-16 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 2, 12 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section M Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7-18 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10, 11 falsefalseInvestments14false0us-gaap_CashAndCashEquivalentsPolicyTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Cash equivalents are carried at fair value and include debt securities that, at purchase, have a maturity of three months or less.  Cash equivalents are carried at fair value and include debt securities that, at purchase, have a maturity of three months or less.  falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringA description of a company's cash and cash equivalents accounting policy. An entity shall disclose its policy for determining which items are treated as cash equivalents. Other information that may be disclosed includes (1) the nature of any restrictions on the entity's use of its cash and cash equivalents, (2) whether the entity's cash and cash equivalents are insured or expose the entity to credit risk, (3) the classification of any negative balance accounts (overdrafts), and (4) the carrying basis of cash equivalents (for example, at cost) and whether the carrying amount of cash equivalents approximates fair value. Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. In addition, cash equivalents include short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. For a bank, may include explanation and amount of requirement to maintain reserves against deposits.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Financial Reporting Release (FRR) -Number 203 -Paragraph 02-03 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 8, 9, 10 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Technical Practice Aid (TPA) -Number 2110 -Paragraph 6 falsefalseCash and Cash Equivalents15false0us-gaap_BusinessCombinationsPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The FASB issued new accounting guidance related to business combinations and noncontrolling interests acquired after December 15, 2008. In April 2009, the FASB issued additional guidance related to accounting for assets acquired and liabilities assumed in a business combination that arise from contingencies. The Company adopted this guidance following the Company obtaining control of Paris Re on the Acquisition Date. The transaction was accounted for as an acquisition method business combination with the purchase price allocated to identifiable assets and liabilities, including certain intangible assets, based on their estimated fair value at the Acquisition Date. The fair value of noncontrolling interests was also recorded at fair value at the Acquisition Date. The estimates of fair values for assets and liabilities assumed were determined by management based on various market and income analyses and appraisals. All costs associated with the acquisition were expensed as incurred. The FASB issued new accounting guidance related to business combinations and noncontrolling interests acquired after December 15, 2008. In April 2009, thefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes how the entity accounts for completed business combinations (purchase method, acquisition method or combination of entities under common control). The policy description may include a general discussion of the purchase method or acquisition method of accounting (including for example, the treatment accorded contingent consideration, the identification of assets and liabilities, the purchase price allocation process, how the fair values of acquired assets and liabilities are determined) and the entity's specific application thereof. An entity that acquires another entity in a leveraged buyout transaction also should disclose the accounting policy followed by the acquiring entity in determining the basis used to value its interest in the acquired entity, and the rationale for that accounting policy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 7 -Subparagraph a, b, c, d Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141 -Paragraph 9, 10, 11, 12, 13 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 88-16 -Section SEC Observer Comments Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 6 falsefalseBusiness Combinations16false0us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Goodwill represents the excess of the purchase price over the fair value of the net assets acquired of PartnerRe SA, Winterthur Re and Paris Re. The Company assesses the appropriateness of its valuation of goodwill on at least an annual basis. If, as a result of the assessment, the Company determines that the value of its goodwill is impaired, goodwill will be written down in the period in which the determination is made. Goodwill represents the excess of the purchase price over the fair value of the net assets acquired of PartnerRe SA, Winterthur Re and Paris Re. The CompanyfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes an entity's accounting policy for goodwill. This accounting policy also may address how an entity assesses and measures impairment of goodwill, how reporting units are determined, how goodwill is allocated to such units, and how the fair values of the reporting units are determined.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 18-23, 26, 34 falsefalseGoodwill17false0us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Intangible assets represent the fair value adjustments related to unpaid losses and loss expenses and unearned premiums, as well as the fair values of renewal rights and U.S. licenses all arising from the acquisition of Paris Re. Definite-lived intangible assets are amortized over their useful lives, generally ranging from two to eleven years. The Company recognizes the amortization of all intangible assets in the Consolidated Statement of Operations. Indefinite-lived intangible assets are not subject to amortization. The carrying values of intangible assets are regularly reviewed for indicators of impairment. Impairment is recognized if the carrying value of the intangible assets is not recoverable from its undiscounted cash flows and is measured as the difference between the carrying value and the fair value. Intangible assets represent the fair value adjustments related to unpaid losses and loss expenses and unearned premiums, as well as the fair values of renewalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes an entity's accounting policy for intangible assets. This accounting policy may address both intangible assets subject to amortization and those that are not. The following also may be disclosed: (1) a description of intangible assets (2) the estimated useful lives of those assets (3) the amortization method used (4) how the entity assesses and measures impairment of such assets (5) how future cash flows are estimated (6) how the fair values of such asset are determined.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 11-17 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 7-18, 22 falsefalseIntangible Assets18false0us-gaap_IncomeTaxPolicyTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Certain subsidiaries and branches of the Company operate in jurisdictions where they are subject to taxation. Current and deferred income taxes are charged or credited to net income, or, in certain cases, to accumulated other comprehensive income, based upon enacted tax laws and rates applicable in the relevant jurisdiction in the period in which the tax becomes accruable or realizable. Deferred income taxes are provided for all temporary differences between the bases of assets and liabilities used in the Consolidated Balance Sheets and those used in the various jurisdictional tax returns. When Management's assessment indicates that it is more likely than not that deferred income tax assets will not be realized, a valuation allowance is recorded against the deferred tax assets. The Company recognizes a tax benefit relating to uncertain tax positions only where the position is more likely than not to be sustained assuming examination by tax authorities. A liability must be recognized for any tax benefit (along with any interest and penalty, if applicable) claimed in a tax return in excess of the amount allowed to be recognized in the financial statements under U.S. GAAP.  Certain subsidiaries and branches of the Company operate in jurisdictions where they are subject to taxation. Current and deferred income taxes are charged orfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes an entity's accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 4 -Paragraph 11 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 48 -Paragraph 20 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 6-34, 43, 47, 49 falsefalseIncome Taxes19false0us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The reporting currency of the Company is the U.S. dollar. The national currencies of the Company's subsidiaries and branches are generally their functional currencies, except for the Company's Bermuda subsidiaries and its Swiss subsidiaries and branch, whose functional currencies are the U.S. dollar. In translating the financial statements of those subsidiaries or branches whose functional currency is other than the U.S. dollar, assets and liabilities are converted into U.S. dollars using the rates of exchange in effect at the balance sheet dates, and revenues and expenses are converted using the average foreign exchange rates for the period. The effect of translation adjustments are reported in the Consolidated Balance Sheets as currency translation adjustment, a separate component of accumulated other comprehensive income. In recording foreign currency transactions, revenue and expense items are converted into the functional currency at the average rates of exchange for the period. Assets and liabilities originating in currencies other than the functional currency are translated into the functional currency at the rates of exchange in effect at the balance sheet dates. The resulting foreign exchange gains or losses are included in net foreign exchange gains and losses in the Consolidated Statements of Operations. The Company also records realized and unrealized foreign exchange gains and losses on certain hedged items in net foreign exchange gains and losses in the Consolidated Statements of Operations (see Note 2(n)).  The reporting currency of the Company is the U.S. dollar. The national currencies of the Company's subsidiaries and branches are generally their functionalfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes a reporting enterprise's accounting policy for (1) transactions denominated in a currency other than the reporting enterprise's functional currency, (2) translating foreign currency financial statements that are incorporated into the financial statements of the reporting enterprise by consolidation, combination, or the equity method of accounting, and (3) remeasurement of the financial statements of a foreign reporting enterprise in a hyperinflationary economy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 52 -Paragraph 5, 7-20, 80 falsefalseTranslation of Foreign Currencies20false0us-gaap_DerivativesPolicyTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Derivatives Used in Hedging Activities The Company utilizes derivative financial instruments as part of its overall currency risk management strategy. The Company recognizes all derivative financial instruments, including embedded derivative instruments, as either assets or liabilities in the Consolidated Balance Sheets and measures those instruments at fair value. On the date the Company enters into a derivative contract, Management designates whether the derivative is to be used as a hedge of an identified underlying exposure (a designated hedge). The accounting for gains and losses associated with changes in the fair value of a derivative and the effect on the Consolidated Financial Statements depends on its hedge designation and whether the hedge is highly effective in achieving offsetting changes in the fair value of the asset or liability being hedged. The derivatives employed by the Company to hedge currency exposure related to fixed income securities and derivatives employed by the Company to hedge currency exposure related to other reinsurance assets and liabilities, except for any hedges of the Company's net investment in non-U.S. dollar functional currency subsidiaries and branches, are not designated as hedges. The changes in fair value of the non-designated hedges are recognized in net foreign exchange gains and losses in the Consolidated Statements of Operations. As part of its overall strategy to manage its level of currency exposure, from time to time the Company uses forward foreign exchange derivatives to hedge or partially hedge the net investment in certain non-U.S. dollar functional currency subsidiaries and branches. The Company also uses from time to time interest rate derivatives to mitigate exposure to interest rate volatility. These derivatives have been designated as net investment hedges, and accordingly, the changes in fair value of the derivative and the hedged item related to foreign currency are recognized in currency translation adjustment in the Consolidated Balance Sheets. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. In this documentation, the Company specifically identifies the asset or liability that has been designated as a hedged item and states how the hedging instrument is expected to hedge the risks related to the hedged item. The Company formally measures effectiveness of its designated hedging relationships, both at the hedge inception and on an ongoing basis. The Company assesses the effectiveness of its designated hedges using the period-to-period dollar offset method on an individual currency basis. If the ratio obtained with this method is within the range of 80% to 125%, the Company considers the hedge effective. The time value component of the designated net investment hedges is included in the assessment of hedge effectiveness. The Company will discontinue hedge accounting prospectively if it is determined that the derivative is no longer effective in offsetting changes in the fair value of a hedged item. To the extent that the Company discontinues hedge accounting related to its net investment in non-U.S. dollar functional currency of subsidiaries and branches, because, based on Management's assessment, the derivative no longer qualifies as an effective hedge, the derivative will continue to be carried in the Consolidated Balance Sheets at its fair value, with changes in its fair value recognized in net foreign exchange gains and losses. Other Derivatives The Company's investment strategy allows for the use of derivative instruments, subject to strict limitations. The Company utilizes various derivative instruments such as foreign exchange forward contracts, foreign currency option contracts, futures contracts and credit default swaps, for the purpose of managing overall currency risk, market exposures and portfolio duration and hedging certain investments, or enhancing investment performance that would be allowed under the Company's investment policy if implemented in other ways. These instruments are recorded at fair value as assets and liabilities in the Consolidated Balance Sheets. Changes in fair value are included in net realized and unrealized investment gains and losses in the Consolidated Statements of Operations and changes in the fair value of foreign currency option contracts and foreign exchange forward contracts are included in net foreign exchange gains and losses in the Consolidated Statements of Operations. Margin balances required by counterparties, which are equal to a percentage of the total value of open futures contracts, are included in cash and cash equivalents. The Company has entered into weather and longevity related transactions that are structured as derivatives, which are recorded at fair value with the changes in fair value reported in net realized and unrealized investment gains and losses in the Consolidated Statements of Operations. The Company has entered into total return and interest rate swaps. Margins related to these swaps are included in other income or loss in the Consolidated Statements of Operations and any changes in the fair value of the swaps are included in net realized and unrealized investment gains and losses in the Consolidated Statements of Operations.  Derivatives Used in Hedging Activities The Company utilizes derivative financial instruments as part of its overall currency risk management strategy. ThefalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDescribes an entity's accounting policies for its derivative instruments and hedging activities. Disclosure may include: (1) Each method used to account for derivative financial instruments and derivative commodity instruments ("derivatives"); (2) the types of derivatives accounted for under each method; (3) the criteria required to be met for each accounting method used, including a discussion of the criteria required to be met for hedge or deferral accounting and accrual or settlement accounting (for example: whether and how risk reduction, correlation, designation, and effectiveness tests are applied); (4) the accounting method used if the criteria specified for hedge accounting are not met; (5) the method used to account for termination of derivatives designated as hedges or derivatives used to affect directly or indirectly the terms, fair values, or cash flows of a designated item; (6) the method used to account for derivatives when the designated item matures, is sold, is extinguished, or is terminated. In addition, the method used to account for derivatives designated to an anticipated transaction, when the anticipated transaction is no longer likely to occur; and (7) where and when derivatives, and their related gains (losses) are reported in the statement of financial position, cash flows, and results of operations and (8) an accounting policy decision to offset fair value amounts with counterparties. An entity should also consider describing its embedded derivatives, and the method(s) used to determine the fair values of derivatives and any significant assumptions used in such valuations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph n -Article 4 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 39 -Paragraph 10 falsefalseDerivatives21false0pre_TreasurySharesPolicyTextBlockprefalsenadurationDescribes the policies employed by the entity to account for repurchases of common shares, reissuances and gains or losses on...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Common shares repurchased by the Company and not cancelled are classified as treasury shares, and are recorded at cost. This results in a reduction of shareholders’ equity in the Consolidated Balance Sheets. When shares are reissued from treasury, the Company uses the average cost method to determine the cost of the reissued shares. Gains on sales of treasury shares are credited to additional paid-in capital, while losses are charged to additional paid-in capital to the extent that previous net gains from sales of treasury shares are included therein, otherwise losses are charged to retained earnings. Common shares repurchased by the Company and not cancelled are classified as treasury shares, and are recorded at cost. This results in a reduction offalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes the policies employed by the entity to account for repurchases of common shares, reissuances and gains or losses on sales of such shares.No authoritative reference available.falsefalseTreasury Shares22false0us-gaap_EarningsPerSharePolicyTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00Diluted net income per common share is defined as net income available to common shareholders divided by the weighted average number of common shares and common share equivalents outstanding, calculated using the treasury stock method for all potentially dilutive securities. Net income available to common shareholders is defined as net income less preferred share dividends. When the effect of dilutive securities would be anti-dilutive, these securities are excluded from the calculation of diluted net income per share. Basic net income per share is defined as net income available to common shareholders divided by the weighted average number of common shares outstanding for the period, giving no effect to dilutive securities.  Diluted net income per common share is defined as net income available to common shareholders divided by the weighted average number of common shares andfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDiscloses the methodology and assumptions used to compute basic and diluted earnings (loss) per share for each class of common stock and participating security. Addresses all significant policy factors, including any antidilutive items that have been excluded from the computation and takes into account stock dividends, splits and reverse splits that occur after the balance sheet date of the latest reporting period but before the issuance of the financial statements.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 40 -Subparagraph a Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 6, 8-16, 60 falsefalseNet Income per Common Share23false0us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The Company currently uses five types of share-based compensation: share options, restricted shares (RS), restricted share units (RSUs), share-settled share appreciation rights (SSARs) and shares issued under the Company’s employee share purchase plans. The majority of the Company’s share-based compensation awards qualify for equity classification. The fair value of the compensation cost is measured at the grant date and is expensed over the period for which the employee is required to provide services in exchange for the award. Forfeiture benefits are estimated at the time of grant and incorporated in the determination of share-based compensation costs. Awards granted to employees who are eligible for retirement and do not have to provide additional services are expensed at the date of grant. Those share-based compensation awards that do not meet the equity classification criteria, are classified as liability awards. Liability-classified awards are recorded at fair value in the Accounts payable, accrued expenses and other in the Consolidated Balance Sheets with changes in fair value relating to the vested portion of the award recorded in the Consolidated Statements of Operations. The Company currently uses five types of share-based compensation: share options, restricted shares (RS), restricted share units (RSUs), share-settled sharefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis element describes an entity's accounting policy for stock option and stock incentive plans. This disclosure may include (1) the types of stock option or incentive plans sponsored by the entity (2) the groups that participate in (or are covered by) each plan (3) significant plan provisions and (4) how stock compensation is measured, and the methodologies and significant assumptions used to determine that measurement.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph A240 -Subparagraph a Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 06-11 -Paragraph 7 falsefalseShare-Based Compensation24false0us-gaap_PensionAndOtherPostretirementPlansPensionsPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The Company recognizes an asset or a liability in the Consolidated Balance Sheets for the funded status of its defined benefit plans that are overfunded or underfunded, respectively, measured as the difference between the fair value of plan assets and the pension obligation and recognizes changes in the funded status of defined benefit plans in the year in which the changes occur as a component of accumulated other comprehensive income, net of tax. The Company recognizes an asset or a liability in the Consolidated Balance Sheets for the funded status of its defined benefit plans that are overfundedfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes an entity's accounting policy for its pension plans. This disclosure may address (1) the types of plans sponsored by the entity (2) groups that participate in (or are covered by) each plan (3) how plan assets, liabilities and expenses are measured, including the use of any actuaries and (4) significant assumptions used by the entity to value plan assets and liabilities and how such assumptions are derived.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 158 -Paragraph 4, 5, 6, 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph a Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5, 6, 7, 9, 11, 12, 13 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 15-19, 63, 64 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph q Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 8 -Subparagraph m falsefalsePensions25false0us-gaap_ConsolidationVariableInterestEntityPolicyus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The Company is involved in the normal course of business with variable interest entities (VIEs) as a passive investor in certain limited partnerships, fixed maturity investments and asset-backed securities, that are issued by third party VIEs. Prior to January 1, 2010, under then effective guidance, the Company performed a quantitative assessment upon initial involvement in a VIE to determine whether it was the primary beneficiary of, and required to consolidate, the VIE. Subsequent to January 1, 2010, in accordance with revised guidance, the Company performs a qualitative assessment at the date when it becomes initially involved in the VIE followed by ongoing reassessments related to its involvement in VIEs. The Company’s maximum exposure to loss with respect to these investments is limited to the investment carrying amounts reported in the Company’s Consolidated Balance Sheets and any unfunded commitments. The Company also has three indirect wholly-owned subsidiaries, PartnerRe Finance A LLC, PartnerRe Finance B LLC and PartnerRe Finance II Inc., that are considered to be VIEs, which were utilized to issue the Company’s Senior Notes and Capital Efficient Notes (CENts). The Company determined that it was not the primary beneficiary of any of these VIEs as of December 31, 2010. As a result, the Company has not consolidated PartnerRe Finance A LLC, PartnerRe Finance B LLC and PartnerRe Finance II Inc., and has reflected the debt issued by the Company related to the Senior Notes and CENts as liabilities in the Consolidated Balance Sheets (see Note 11). The interest on the debt related to the Senior Notes and CENts is reported as interest expense in the Consolidated Statements of Operations. The Company is involved in the normal course of business with variable interest entities (VIEs) as a passive investor in certain limited partnerships, fixedfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDescribes an entity's accounting policy regarding its principles of consolidation for variable interest entities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 46R -Paragraph 14, 15 falsefalseVariable Interest Entities26false0pre_SegmentReportingPolicyTextBlockprefalsenadurationGeneral information about how the Company has organized its operations into the various segments.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00The Company monitors the performance of its operations in three segments, Non-life, Life and Corporate and Other. The Non-life segment is further divided into four sub-segments: North America, Global (Non-U.S.) Property and Casualty (Global (Non-U.S.) P&C), Global (Non-U.S.) Specialty and Catastrophe. Segments and sub-segments represent markets that are reasonably homogeneous in terms of geography, client types, buying patterns, underlying risk patterns or approach to risk management. During the fourth quarter of 2010, the Company redefined its financial reporting segments following the completion of its integration of Paris Re into its other Non-life sub-segments and changes in management responsibilities for certain lines of business and treaties. As a result, segment data for prior periods has been recast to conform to the current year presentation (see Note 22). The Company monitors the performance of its operations in three segments, Non-life, Life and Corporate and Other. The Non-life segment is further dividedfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringGeneral information about how the Company has organized its operations into the various segments.No authoritative reference available.falsefalseSegment Reporting27false0us-gaap_DescriptionOfNewAccountingPronouncementsNotYetAdoptedus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00In January 2010, the FASB issued new accounting guidance which requires the Company to disclose additional information about its fair value measurements at a greater level of disaggregation related to Level 3 activity, which will be effective for interim and annual periods beginning after December 15, 2010. In October 2010, the FASB issued new accounting guidance clarifying that only acquisition costs related directly to the successful acquisition of new or renewal insurance contracts may be capitalized. Those acquisition costs that may be capitalized include incremental direct costs, such as commissions, and a portion of salaries and benefits of certain employees who are involved in underwriting and policy issuance, that are directly related to time spent on an acquired contract. This guidance is effective for interim and annual periods beginning after December 15, 2011, with early adoption permitted at the beginning of an entity’s annual reporting period. The Company is currently evaluating the impact of the adoption of this guidance on its consolidated shareholders’ equity or net income.In January 2010, the FASB issued new accounting guidance which requires the Company to disclose additional information about its fair value measurements at afalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringFor a new accounting pronouncement that has been issued but not yet adopted, an entity's disclosure should (1) describe the new pronouncement, the date that adoption is required and the date that the entity plans to adopt, if earlier; (2) discuss the methods of adoption allowed by the pronouncement and the method expected to be utilized by the entity, if determined; (3) discuss the impact that adoption of the pronouncement is expected to have on the financial statements of the entity, unless such impact is not known or reasonably estimable (in which case, a statement to that effect should be made) and; (4) disclose the potential impact of other significant matters that the entity believes might result from the adoption of the pronouncement (for example, technical violations of debt covenant agreements and planned or intended changes in business practices.)Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 11 -Section M falsefalseRecent Accounting Pronouncements126Significant Accounting Policies (Policies)UnKnownUnKnownUnKnownUnKnownfalsetrue