Average Percentage of Unrealized Loss Versus Amortized Cost for Below Investment Grade Securities

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- Definition

Average Percentage of Unrealized Loss Versus Amortized Cost for Investment Grade Securities

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- Definition

Fair value of cash and securities pledged to derivative counterparties.

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Fair value of securities deposited with governmental authorities.

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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount 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).

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Amount of 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.

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- Definition

Amount of investments classified as other.

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Investments - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 1	$ 0	$ 1
Securities fair value	23	23
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	$ 90	106
Average Percentage of Unrealized Loss Versus Amortized Cost for Below Investment Grade Securities	6.00%
Average Percentage of Unrealized Loss Versus Amortized Cost for Investment Grade Securities	8.00%
Investment Portfolio [Member]
Schedule of Investments [Line Items]
Fair Value of Cash and Securities Pledged to Derivative Counterparties	$ 61	64
Interest Rate Contract [Member]
Schedule of Investments [Line Items]
Other investments	84	80
Fixed Income Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	1	0
Debt Securities, Available-for-sale, Unrealized Loss Position	1,147	1,183
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	90	106
Fixed Income Securities [Member] \| Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position	630	559
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	54	63
Fixed Income Securities [Member] \| Corporate Debt Securities [Member] \| External Credit Rating, Investment Grade
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	53
Fixed Income Securities [Member] \| Corporate Debt Securities [Member] \| External Credit Rating, Non Investment Grade [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1
Fixed Income Securities [Member] \| Residential Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	1	0
Debt Securities, Available-for-sale, Unrealized Loss Position	132	132
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	16	19
Fixed Income Securities [Member] \| Asset-backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale, Unrealized Loss Position	111	203
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	5	5
Reported Value Measurement [Member]
Schedule of Investments [Line Items]
Other investments	65	$ 61
Commitments [Member] \| Partnership Interest [Member]
Schedule of Investments [Line Items]
Other investments	$ 57