Related party transactions - Investments managed by related parties (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Related Party Transaction [Line Items]
Investments in related party investment funds, at fair value	$ 309.0	$ 909.6
Total investments	5,738.0	4,529.9
Affiliated entity
Related Party Transaction [Line Items]
Investments in related party investment funds, at fair value	309.0	909.6
Third Point Optimized Credit Portfolio	500.7	0.0
Total investments	809.7	909.6
Affiliated entity \| Third Point Enhanced LP
Related Party Transaction [Line Items]
Investments in related party investment funds, at fair value	280.3	878.2
Affiliated entity \| Third Point Venture Offshore Fund I LP
Related Party Transaction [Line Items]
Investments in related party investment funds, at fair value	$ 28.7	$ 31.4

Investments In Related Party Investment Funds

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562

+ Details

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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