Derivative Financial Instruments Nature and Amount of Collateral Received From and Posted To Our Derivative Counterparties (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Derivative
Cash Collateral from Counterparties	$ 22.4	$ 8.7
Cash
Derivative
Cash Collateral from Counterparties	22.4	8.7
Fixed Maturity Securities
Derivative
FMS Collateral Posted to Counterparties	30.0	54.0
Cash Collateral Posted to Counterparties	2.7	0.0
Derivative Liabilities Net of Collateral	$ 32.7	$ 54.0

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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

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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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Fair value, after effects of master netting arrangements, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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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.

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