Derivative Financial Instruments Nature and Amount of Collateral Received From and Posted To Our Derivative Counterparties (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivative
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 37.4	$ 49.4
Derivative Liability, Subject to Master Netting Arrangement, Deduction of Financial Instrument Not Offset	39.8	44.7
Cash
Derivative
Cash Collateral from Counterparties	11.1	49.4
Cash Collateral Posted to Counterparties	0.0	5.1
Fixed Maturity Securities
Derivative
Carrying Value of Fixed Maturity Securities Received as Collateral from Counterparties	26.3	0.0
FMS Collateral Posted to Counterparties	$ 39.8	$ 39.6

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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