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Significant Transactions - BAM (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Jul. 01, 2024
Other Significant Transactions [Line Items]
Unrealized loss on deconsolidation of BAM	$ 114.5	$ 0.0	$ 0.0
Operating Segments | Financial Guarantee (HG Global)
Other Significant Transactions [Line Items]
Notes receivable, fair value disclosure	381.7	0.0		$ 387.4
Unrealized loss on deconsolidation of BAM	$ 114.5	$ 0.0	$ 0.0

X

- Definition

Amount of gain (loss) from deconsolidation of subsidiary and derecognition of group of assets constituting transfer of business or nonprofit activity, excluding conveyance of oil and gas mineral rights and transfer of good or service in contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481203/810-10-50-1B

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X

- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

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X

- Definition

Other Significant Transactions [Line Items]

+ References

No definition available.

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