Investment Activity (Impairments of Long-Lived Assets Narrative) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($) property	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($) property
Investments
Real Estate [Line Items]
Impairment of real estate		$ 0.7		$ 0.7
Number of real estate properties, impaired, sold or classified as held for sale \| property		1		1
Senior Living Campuses \| Disposal Group, Held-for-sale, Not Discontinued Operations \| 2025 Disposal Group
Real Estate [Line Items]
Purchase price	$ 39.0		$ 39.0
Rental income	0.7	$ 0.7	1.4	$ 1.4
Net real estate balance	$ 18.8		$ 18.8

Number Of Real Estate Properties, Impaired, Sold Or Classified As Held For Sale

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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