Investments - Net Gains (Losses) on Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fixed-maturities available for sale
Net realized gains (losses) on investments sold or redeemed	$ (10,733)	$ (8,306)	$ 20,842
Change in unrealized gains (losses) on mortgage loans and related derivatives sold or redeemed	915	(3,458)	(8,714)
Net decrease (increase) in expected credit losses	0	0	918
Net unrealized gains (losses) on investments still held
Net unrealized gains (losses) on investments still held	9,958	(53,342)	4,053
Net gains (losses) on investments	140	(65,106)	17,099
Mortgage loans	814	48	0
Net gains (losses) on other financial instruments	9,287	(15,675)	(1,496)
Net gains (losses) on investments and other financial instruments	10,241	(80,733)	15,603
Fixed-maturities available for sale
Fixed-maturities available for sale
Gross realized gains	1,609	2,763	22,766
Gross realized losses	(15,346)	(12,737)	(17,105)
Fixed-maturities available for sale, net	(13,737)	(9,974)	5,661
Trading securities
Fixed-maturities available for sale
Trading securities	(402)	(135)	390
Net unrealized gains (losses) on investments still held
Trading securities	2,308	(27,700)	(7,330)
Equity securities
Fixed-maturities available for sale
Equity securities	3,350	1,655	10,820
Net unrealized gains (losses) on investments still held
Equity securities	7,625	(25,255)	10,210
Other investments
Fixed-maturities available for sale
Other investments	56	148	3,971
Net unrealized gains (losses) on investments still held
Other investments	$ 25	$ (387)	$ 1,173

Change in Unrealized Gains (Losses) On Investments Sold or Redeemed

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Amount of unrealized holding gain (loss) recognized in the income statement for investments in equity securities and securities classified as trading.

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Amount of the change in unrealized holding gain (loss) recognized in the income statement for investments in equity securities.

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Gain (Loss) On Financial Instruments

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This concept represents the gains and losses on investments and other financial instruments for the period excluding the impact of changes in the present value of insurance claims and recoveries on insured credit derivatives and VIEs, based on the company's ongoing insurance loss monitoring, which are a component of segment expenses. Also includes other than temporarily impaired losses recognized in earnings.

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Other Investments, Change in Unrealized Holding Gain (Loss)

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Other than Temporary Impairment Losses, Investments, Expected Credit Losses

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This amount represents the net realized gains (losses) on all fixed-maturities, equity, trading, short-term, and other-invested assets securities, excluding other-than-temporary impairments and net unrealized gains (losses) on investment securities.

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No definition available.

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Securities, Trading, Realized Gain (Loss)

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Unrealized Gains (Losses) on Investments

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of realized gain 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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Amount of realized gain (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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Amount of realized 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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Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized and unrealized gain (loss) on investment.

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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