Balance Sheet Parentheticals (Parentheticals) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fixed-maturities available for sale—at amortized cost	$ 4,564,616	$ 4,549,534
Debt Securities, Trading, Amortized Cost	270,551	297,505
Available-for-sale Equity Securities, Amortized Cost Basis	86,456	125,311
Reinvested cash collateral held under securities lending agreements	$ 14,808	$ 25,561
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Common Stock, Shares Authorized	485,000	485,000
Common Stock, Shares, Issued	208,364	219,123
Common Stock, Shares, Outstanding	190,387	201,164
Treasury Stock, Shares	17,977	17,959

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

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Amortized cost of investments in debt securities 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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