Fair Value Measurements - Schedule of Financial Instruments Not Measured at Fair Value on our Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Carrying value
Fair value of financial assets and liabilities
Loans receivable	$ 1,329.8	$ 828.5
Mortgages payable	38.7	81.3
Notes and bonds payable	25,198.0	22,938.7
Fair value
Fair value of financial assets and liabilities
Loans receivable	1,316.6	835.1
Mortgages payable	38.1	80.0
Notes and bonds payable	$ 24,205.7	$ 21,593.5

Fair value portion of notes payable.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details