Derivative Financial Instruments (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gains or losses reclassified into earnings	$ 0	$ 0	$ 0	$ 0
Estimated net gain (loss) to be reclassified into net income within the next twelve months relating to cash flow hedges			$ 2,700,000
Maximum length of time over which exposure was being hedged			3 months
Net investment gains (losses) recognized in AOCI	$ (135,600,000)	$ 129,900,000	$ (36,300,000)	$ 66,800,000

Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Before Reclassification, After Ta

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480870/815-30-50-1

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- References

No definition available.

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- Definition

The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480870/815-30-50-1

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- Definition

Maximum period of hedging exposure to variability in future cash flows for forecasted transaction of foreign currency cash flow hedge, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes forecasted transaction for payment of variable interest on existing financial instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-SubTopic 30
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480870/815-30-50-1

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