Derivative Financial Instruments Nature and Amount of Collateral Received From and Posted To Our Derivative Counterparties (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Derivative
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 34.3	$ 37.4
Derivative Liability, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	50.6	39.8
Cash
Derivative
Cash Collateral from Counterparties	3.4	11.1
Cash Collateral Posted to Counterparties	0.0	0.0
Fixed Maturity Securities
Derivative
Carrying Value of Fixed Maturity Securities Posted as Collateral to Counterparties	30.9	26.3
FMS Collateral Posted to Counterparties	$ 50.6	$ 39.8

Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset, subject to master netting arrangement or similar agreement and not elected or qualified to offset, deducted from derivative asset.

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Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities.

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