Derivatives - Counterparty collateral (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Cash \| Collateral deposits on derivative contracts for the benefit of the company
Derivatives
Financial assets pledged as collateral	$ 50.0	$ 42.2
Government securities
Derivatives
Financial assets pledged as collateral	1,015.1	492.3
Government securities \| Collateral deposits on derivative contracts for the benefit of the company
Derivatives
Financial assets pledged as collateral	1,015.1	492.3
Holding company cash and investments \| Collateral deposits on derivative contracts for the benefit of the derivative counterparties
Derivatives
Financial assets pledged as collateral	344.4	337.0
Amount of collateral originally required for deposit	271.6	270.3
Amount of collateral deposits attributable to changes in fair value since the most recent reset date	$ 72.8	$ 66.7

The amount of financial assets pledged as collateral for derivative liabilities at fair value attributable to the changes in value since the most recent reset date.

No definition available.

+ Details

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Period Type:	instant

- Definition

The amount of financial assets pledged as collateral for derivative liabilities at fair value attributable to the original deposit required to enter into the contract.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The amount of financial assets that the entity has pledged as collateral for liabilities or contingent liabilities, including amounts that have been reclassified in accordance with paragraph 3.2.23(a) of IFRS 9. [Refer: Classes of contingent liabilities [domain]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 14
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_14_a&doctype=Standard
-URIDate 2024-03-27

+ Details

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- Details

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- Details

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- Details

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- Details

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