Consolidated Balance Sheets (Parenthetical)(USD ($)) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fixed maturity investments trading, amortized cost	$ 6,035,240	$ 6,065,350
Equity securities trading - cost	$ 791,206us-gaap_TradingSecuritiesEquityCost	$ 647,301us-gaap_TradingSecuritiesEquityCost
Common stock, shares issued	100,775,256us-gaap_CommonStockSharesIssued	103,477,452us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	96,195,482us-gaap_CommonStockSharesOutstanding	100,253,646us-gaap_CommonStockSharesOutstanding
Treasury stock (shares)	4,579,774us-gaap_TreasuryStockShares	3,223,806us-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.

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

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Amortized cost of investments in debt securities classified as trading.

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

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No definition available.

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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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