Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Fixed maturities - available for sale, amortized cost	$ 11,255,282	$ 10,248,650
Fixed maturities - available for sale, at market value, allowance for credit loss	23,783	1,566
Short-term investments, cost	$ 503,452	$ 708,043
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,000	3,000
Common stock, shares issued	1,000	1,000
Common stock, shares outstanding	1,000	1,000
Accumulated other comprehensive income (loss), deferred income tax expense (benefit)	$ 60,978	$ 71,080
Senior Notes [Member] \| Senior Notes 4.868% [Member]
Debt instrument, maturity date	Jun. 01, 2044	Jun. 01, 2044
Senior Notes [Member] \| Senior Notes 3.5% [Member]
Debt instrument, maturity date	Oct. 15, 2050	Oct. 15, 2050
Long Term Subordinated Debt [Member] \| Subordinated Notes 6.6% [Member]
Debt instrument, maturity date	May 01, 2067	May 01, 2067

Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss).

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Other Short Term Investments Cost

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

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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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Amount of allowance for credit loss on 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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