Insurance Liabilities (Liability for Future Policy Benefits - Narrative) (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Mean Reversion Rate	0.0450		0.0400
Participating whole life insurance (3)
Participating Insurance, Percentage of Gross Insurance in Force	3.00%	3.00%
Participating Insurance, Percentage of Premium Income	38.00%	39.00%
Participating whole life insurance (3) \| Minimum
Liability for Future Policy Benefits, Interest Rate	3.50%
Participating whole life insurance (3) \| Maximum
Liability for Future Policy Benefits, Interest Rate	4.00%

Mean Reversion Rate

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- Definition

Rate of interest used to calculate the liability for future policy benefits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480081/944-40-50-6

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- Definition

Percentage of participating insurance contract to insurance contracts in force.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479756/944-50-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(14)(b)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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- Definition

Percentage of participating insurance to premium income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479756/944-50-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(14)(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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