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Net Investment (Losses) Gains (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment losses	$ (150,455)	$ (394,832)	$ (62,476)	$ (1,365,064)
Income tax benefit	32,090	79,168	11,626	288,847
Noncontrolling interests	0	0	(1)	(1)
Total change in unrealized gains	(118,365)	(315,664)	(50,851)	(1,076,218)
Debt securities
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment losses	(136,388)	(385,503)	(57,293)	(1,335,413)
Fixed maturity securities with allowance for expected credit losses
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment losses	(10,244)	(4,005)	(3,094)	(20,590)
Investment funds
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment losses	(3,217)	(5,031)	(818)	(7,863)
Other
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized investment losses	$ (606)	$ (293)	$ (1,271)	$ (1,198)

X

- Definition

Amount, before tax and after adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-11

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