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Investments - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Investments, Debt and Equity Securities [Abstract] |
Gross realized investment gains | $ 13

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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=118939692&loc=d3e27357-111563 + Details
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- References No definition available. + Details
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