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Segment Information - Assets by Segment (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Segment Reporting Information [Line Items]
Segment assets	$ 35,768.5	$ 36,289.6
Assets held for sale	0.0	512.4
Disposal Group, Held-for-Sale, Not Discontinued Operations
Segment Reporting Information [Line Items]
Proceeds from sale of property			$ 126.0
Disposal Group, Held-for-Sale, Not Discontinued Operations \| Property In Miami, Florida
Segment Reporting Information [Line Items]
Held-for-sale property	46.0	46.0
Corporate and Other
Segment Reporting Information [Line Items]
Segment assets	1,527.1	2,283.7
Global Lifestyle \| Operating Segments
Segment Reporting Information [Line Items]
Segment assets	29,083.4	28,846.7
Global Housing \| Operating Segments
Segment Reporting Information [Line Items]
Segment assets	$ 5,158.0	$ 5,159.2