Condensed Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets
Fixed maturities, amortized cost	$ 12,920,945	$ 13,489,633
Short-term investments, amortized cost	20,054	25,699
Equities, cost	1,115,408us-gaap_TradingSecuritiesEquityCost	843,429us-gaap_TradingSecuritiesEquityCost
Funds held - directly managed, cost	581,850pre_FundsHeldDirectlyManagedCost	600,379pre_FundsHeldDirectlyManagedCost
Shareholders’ Equity
Common shares, par value	$ 1	$ 1
Common shares, shares issued	87,237,220us-gaap_CommonStockSharesIssued	87,237,220us-gaap_CommonStockSharesIssued
Preferred shares, par value	$ 1	$ 1
Number of preferred shares issued	34,150,000us-gaap_PreferredStockSharesIssued	34,150,000us-gaap_PreferredStockSharesIssued
Preferred shares, shares outstanding	34,150,000us-gaap_PreferredStockSharesOutstanding	34,150,000us-gaap_PreferredStockSharesOutstanding
Aggregate liquidation value	$ 853,750	$ 853,750
Common shares held in treasury, shares	39,572,572us-gaap_TreasuryStockShares	39,400,936us-gaap_TreasuryStockShares

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In the event of liquidation of the Company, the holders of outstanding preferred shares would have preference over the common shareholders and would receive a distribution of $25.00 per share, plus accrued and unpaid dividends.

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Amortized cost of investments in debt securities classified as trading.

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Amortized cost of short-term investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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