CONSOLIDATED BALANCE SHEETS (Parentheticals) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Statement Of Financial Position Parenthetical [Abstract]
Fixed maturities available for sale, at amortized cost	$ 9,304,357	$ 8,771,988
Short-term investments available for sale, at amortized cost	807,872	913,488
Investment of funds received under securities lending agreements, amortized cost	44,695	69,682
Other investments (cost)	226,089	252,590
Common shares (issued)	163,267,317	160,073,616
TALF investments amortized cost	376,889	389,200
TALF borrowings,at par	314,371	326,219
Common shares par	$ 0.0033	$ 0.0033
Investment in joint venture cost	100,000	100,000
Common shares held in treasury (shares)	30,261,852	20,441,391
Equity securities (cost)	$ 300,335	$ 292,958

Equity securities - available for sale, at cost

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The amortized cost as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

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The amortized cost as of the balance sheet date of short term investments not otherwise specified in the taxonomy that will be realized in a short period of time, usually less than one year.

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Par Value of asset backed securities and commercial mortgage backed securities held as part of the FRBNY Term Asset-Backed Securities Loan Facility ("TALF").

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Amortized cost of asset backed securities and commercial mortgage backed securities held as part of the FRBNY Term Asset-Backed Securities Loan Facility ("TALF").

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This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are classified neither as held-to-maturity nor trading securities.

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-Name FASB Staff Position (FSP)

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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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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This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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Includes other investments and securities that are not at fair value as of the balance sheet date and those that are not accounted for under the equity method.

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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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