Fair Value of Financial Instruments - Schedule of Level 3 Instruments at Fair Value (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Assets
Foreign currency exchange gains	$ 13.3	$ 39.4	$ (10.6)	$ 48.1
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Secured Borrowing on Collateralized Receivables
Liabilities
Beginning balance	41.6	49.3	43.2	51.2
Realized gains	(0.6)	(0.5)	(0.6)	(0.5)
Purchases and issuances	0.0	0.0	0.0	0.0
Sales and settlements	(1.8)	(2.2)	(3.4)	(4.1)
Dispositions of properties	0.0	0.0	0.0	0.0
Other adjustments	0.0	0.0
Ending balance	39.2	46.6	39.2	46.6
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Other Liabilities (Contingent Consideration)
Liabilities
Beginning balance	0.2	0.8	0.2	11.3
Realized gains	0.0	0.0	0.0	0.0
Purchases and issuances	0.3	0.0	0.3	0.0
Sales and settlements	0.0	0.0	0.0	(9.0)
Dispositions of properties	0.0	(2.3)	0.0	(2.3)
Other adjustments	0.0	1.5
Ending balance	0.5	0.0	0.5	0.0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Installment Notes Receivable on MH, net
Assets
Beginning balance	145.3	105.6	139.2	93.9
Foreign currency exchange gains	0.0	0.0	0.0	0.0
Ending balance	150.5	116.3	150.5	116.3
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Installment Notes Receivable on MH, net \| Realized gains / (losses)
Assets
Changes to fair value	(2.9)	(1.4)	(2.8)	(1.6)
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Installment Notes Receivable on MH, net \| Purchases and issuances
Assets
Changes to fair value	11.0	14.3	21.1	27.7
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Installment Notes Receivable on MH, net \| Sales and settlements
Assets
Changes to fair value	(2.9)	(2.2)	(6.8)	(3.7)
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Installment Notes Receivable on MH, net \| Dispositions of properties
Assets
Changes to fair value	0.0	0.0	(0.2)	0.0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Notes Receivable From Real Estate Operators
Assets
Beginning balance	43.7	89.5	44.5	148.5
Foreign currency exchange gains	(0.9)	2.1	(1.7)	2.2
Ending balance	50.9	93.1	50.9	93.1
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Notes Receivable From Real Estate Operators \| Realized gains / (losses)
Assets
Changes to fair value	0.0	0.0	0.0	0.0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Notes Receivable From Real Estate Operators \| Purchases and issuances
Assets
Changes to fair value	8.7	2.5	9.2	4.1
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Notes Receivable From Real Estate Operators \| Sales and settlements
Assets
Changes to fair value	(0.6)	(1.0)	(1.1)	(61.7)
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Notes Receivable From Real Estate Operators \| Dispositions of properties
Assets
Changes to fair value	0.0	0.0	0.0	0.0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Collateralized Receivables, net
Assets
Beginning balance	41.6	49.3	43.2	51.2
Foreign currency exchange gains	0.0	0.0	0.0	0.0
Ending balance	39.2	46.6	39.2	46.6
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Collateralized Receivables, net \| Realized gains / (losses)
Assets
Changes to fair value	(0.6)	(0.5)	(0.6)	(0.5)
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Collateralized Receivables, net \| Purchases and issuances
Assets
Changes to fair value	0.0	0.0	0.0	0.0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Collateralized Receivables, net \| Sales and settlements
Assets
Changes to fair value	(1.8)	(1.9)	(3.4)	(3.1)
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Collateralized Receivables, net \| Dispositions of properties
Assets
Changes to fair value	$ 0.0	$ (0.3)	$ 0.0	$ (1.0)

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Fair value portion of asset recognized for present right to economic benefit.

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Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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