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v3.23.1

Investment Gains and Losses Reported in Consolidated Statements of Income (Detail) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Fixed Maturity Securities |  |
Gross Gains on Sales | $ 0.5 | $ 0.3
Gross Losses on Sales | 0.2 | 8.8
Credit Losses | 0.0 | (4.1)
Mortgage Loans and Other Invested Assets |  |
Gross Gains on Sales | 0.2 | 1.4
Gross Losses on Sales | 0.0 | 0.0
Credit Losses | (0.7) | 0.5
Embedded Derivative in Modified Coinsurance Arrangement | 0.3 | (3.4)
All Other Derivatives | (0.6) | 1.8
Foreign Currency Transactions | 0.6 | (1.5)
Net Investment Gain (Loss) | $ 0.1 | $ (13.8)

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- Definition Amount of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479106/326-30-50-9 + Details
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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-9 + Details
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