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Investments - Net Realized Investment Gains (Losses) (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Investments, Debt and Equity Securities [Abstract] |  |
Gross realized gains on sales available-for-sale securities | $ 0 | $ 1
Gross realized losses on sales available-for-sale securities | (2) | (2)
Net foreign currency gains (losses) | 0 | 1
Change in credit impairment and intent to sell | (5) | (4)
Other net realized gains (losses) (1) | 10 | 1
Net realized investment gains (losses) | $ 3 | $ (3)

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- Definition Net Realized Investment Gains (Losses) + References No definition available. + Details
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- Definition Amount of writeoff of allowance for credit loss 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 -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 9 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563 + Details
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- Definition Amount of realized loss 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 -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563 + Details
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References No definition available. + Details
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- Definition Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124440516&loc=d3e30840-110895 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=125521441&loc=d3e30690-110894 + Details
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