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v3.22.2.2

Investments (Narrative) (Detail) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2022 USD ($) security | Sep. 30, 2021 USD ($) | Dec. 31, 2021 USD ($) security
Schedule Of Investments [Line Items] |  |  |
Fair value of securities on deposit with various regulatory authorities | $ 10 |  | $ 11
Number of securities in unrealized loss position for a continuous 12 month period | security | 140 |  | 36
Rate that a security's fair value is below book value | 5.00% |  | 5.00%
Increase Decrease In Other Net Realized Gains Losses | $ 13 | $ 14 |
Asset Pledged as Collateral [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Fair value of securities pledged as collateral | $ 282 |  | $ 280
Securities In Unrealized Loss Position [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Weighted average contractual maturity period in years for securities in an unrealized loss position | 14 years |  | 11 years
Increase Decrease In Other Net Realized Gains Losses | $ 2 |  |
Debt securities intent to sell impairment | $ 21 |  |
Fair Value Below Book Value Greater Than Five Percent [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Number of securities in unrealized loss position for a continuous 12 month period | security | 135 |  | 7

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- Definition Disclosure regarding factors used to determine that the impairment of securities not categorized as trading securities (hence equal to available for sale and held to maturity securities) where cost exceeds fair value. This item contains disclosure of the number of investment positions in the investments determined to be temporarily impaired. + References No definition available. + Details
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- Definition Percentage that a security's fair value is below its book value on available-for-sale and held-to-maturity securities. This percentage is used as a severity threshold for disclosing information about securities in an unrealized loss position for a continuous 12 month period or longer. + References No definition available. + Details
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- Definition The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969 + Details
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