Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Dec. 31, 2010	Dec. 31, 2009
Consolidated Balance Sheets
Fixed maturity securities, available-for-sale, amortized cost (in dollars)	$ 9,274,718	$ 8,943,909
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	183,744,655	184,162,896
Common stock, shares outstanding	183,744,655	184,162,896
Accumulated other comprehensive income, tax provision (benefit) (in dollars)	$ 18,341	$ 58,551
Deferred equity compensation, shares	181,818	181,818

Represents the number of deferred shares that are held in the company's supplemental employee retirement plan and have not been issued to employees or officers.

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This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are classified neither as held-to-maturity nor trading securities.

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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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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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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 shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Excludes common shares repurchased by the entity and held as Treasury shares. Shares outstanding equals shares issued minus shares held in treasury. Does not include common shares that have been repurchased.

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-Publisher AICPA

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The amount as of the balance sheet date of the estimated future tax effects arising from unrealized gain on items included in other comprehensive income which will increase future taxable income when such gain is realized.

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