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Fixed Maturity Securities In An Unrealized Loss Position (Non-Investment Grade Fixed Maturity Securities) (Details) - External Credit Rating, Noninvestment Grade $ in Thousands	Sep. 30, 2025 USD ($)
Debt Securities, Available-for-sale [Line Items]
Number of Securities	125
Aggregate Fair Value	$ 272,127
Gross Unrealized Loss	$ 197,338
Foreign government
Debt Securities, Available-for-sale [Line Items]
Number of Securities	75
Aggregate Fair Value	$ 189,418
Gross Unrealized Loss	$ 194,357
Corporate
Debt Securities, Available-for-sale [Line Items]
Number of Securities	28
Aggregate Fair Value	$ 51,508
Gross Unrealized Loss	$ 1,533
State and municipal
Debt Securities, Available-for-sale [Line Items]
Number of Securities	6
Aggregate Fair Value	$ 28,795
Gross Unrealized Loss	$ 1,256
Mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Number of Securities	15
Aggregate Fair Value	$ 2,404
Gross Unrealized Loss	$ 191
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Number of Securities	1
Aggregate Fair Value	$ 2
Gross Unrealized Loss	$ 1

X

- Definition

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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