Unaudited Condensed Consolidated Balance Sheets (Parenthetical)(USD ($)) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fixed maturity investments trading, amortized cost	$ 6,229,608	$ 6,035,240
Equity securities trading - cost	$ 798,275us-gaap_TradingSecuritiesEquityCost	$ 791,206us-gaap_TradingSecuritiesEquityCost
Common stock, shares issued	100,299,454us-gaap_CommonStockSharesIssued	100,775,256us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	95,444,669us-gaap_CommonStockSharesOutstanding	96,195,482us-gaap_CommonStockSharesOutstanding
Treasury stock (shares)	4,854,785us-gaap_TreasuryStockShares	4,579,774us-gaap_TreasuryStockShares

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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- Definition

Amortized cost of investments in debt securities classified as trading.

+ References

No definition available.

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Cost of investments in equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

No definition available.

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- Definition

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.

+ References

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