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Investments - Gross unrealized losses by unrealized loss position and credit quality (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
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Investment [Line Items] |  |
Total unrealized losses | $ 1,000,000 |
Investment grade |  |
Investment [Line Items] |  |
Fixed income securities with unrealized loss position less than 20% of amortized cost, net | (15,000,000) |
Fixed income securities with unrealized loss position greater than or equal to 20% of amortized cost, net | (15,000,000) |
Total unrealized losses | 30,000,000 | $ 61,000,000
Below investment grade |  |
Investment [Line Items] |  |
Fixed income securities with unrealized loss position less than 20% of amortized cost, net | (24,000,000) |
Fixed income securities with unrealized loss position greater than or equal to 20% of amortized cost, net | (19,000,000) |
Total unrealized losses | 43,000,000 | 35,000,000
Available for sale securities, unrealized losses having loss of less than twenty percent, less than 12 months | (17,000,000) |
Unrealized losses related to securities with unrealized loss position greater than 20% of cost or amortized cost, unrealized loss position of 12 or more consecutive months | 0 |
Fixed income securities |  |
Investment [Line Items] |  |
Fixed income securities with unrealized loss position less than 20% of amortized cost, net | (39,000,000) |
Fixed income securities with unrealized loss position greater than or equal to 20% of amortized cost, net | (34,000,000) |
Total unrealized losses | $ 73,000,000 | $ 96,000,000

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- Definition This item represents the excess of [amortized] cost over fair value of fixed income securities that have been in a loss position for twelve months or longer, and have unrealized loss position greater than 20% of cost or amortized cost for those securities which are categorized neither as held-to-maturity nor trading securities as of the balance sheet date. + References No definition available. + Details
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- Definition The amount of unrealized losses that are related to securities with an unrealized loss position less than 20% of cost or amortized cost. + References No definition available. + Details
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- Definition The amount of unrealized losses that are related to securities with an unrealized loss position greater than 20% of cost or amortized cost. + References No definition available. + Details
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- Definition Available for sale Securities, Unrealized Losses Having Loss of Less than Twenty Percent, Less than 12 Months + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922888-210455 + Details
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- Definition 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. + References No definition available. + Details
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