Other Investments Income

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- Definition

Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on available-for-sale securities.

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Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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Amount of expenses related to the generation of investment income.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

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- Definition

Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(2))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

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- Definition

The sum of the realized and unrealized net gain (loss) on trading securities during the period.

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No definition available.

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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.

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No definition available.

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Amount of gain (loss) realized from securities classified as trading.

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Investments - Summary of Net Investment Income (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investment [Line Items]
Net Realized and Unrealized Gain (Loss) on Trading Securities									$ 0	$ 24	$ (3)
Trading Securities, Realized Gain (Loss)									(18)	7	1
Fixed income securities										183	265
Investment expense									(6)	(6)	(7)
Securities available-for-sale and short-term									103	196	271
Net investment income	$ 53	$ 37	$ 52	$ (21)	$ 42	$ 45	$ 86	$ 55	122	227	273
Gains (losses) on securities held as of reporting date [Member]
Investment [Line Items]
Other Investments Income									18	17	(4)
Available-for-sale Securities [Member]
Investment [Line Items]
Fixed income securities									103
Short-term Investments [Member]
Investment [Line Items]
Fixed income securities									5	17	11
Financing Receivable [Member]
Investment [Line Items]
Fixed income securities									1	1	1
Other Investments [Member]
Investment [Line Items]
Fixed income securities									$ 19	$ 32	$ 2