Derivative Financial Instruments (Narrative) (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gains or losses reclassified into earnings	$ 0	$ 0	$ 0	$ 0
Net investment gains (losses) recognized in AOCI	$ 18,000,000.0	$ (30,600,000)	$ 99,300,000	$ (63,100,000)

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.

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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration