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Derivative Financial Instruments Fair Value Hedges Carrying Amount of Hedged Assets and Liabilities and Cumulative Basis Adjustments (Details) - Interest Rate Swaps - Receive Fixed/Pay Fixed - Designated as Hedging Instrument - Fair Value Hedging - Fixed Maturity Securities - USD ($) $ in Millions | Jun. 30, 2022 | Dec. 31, 2021
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Derivative Instruments and Hedging Activities Disclosures |  |
Hedged Asset, Fair Value Hedge | $ 406.6 | $ 466.3
Hedged Asset, Fair Value Hedge, Cumulative Increase | $ (30.9) | $ 2.0

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- Definition Amount of asset hedged in fair value hedging relationship. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959 + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959 + Details
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