Schedule of Pre-Tax Income (Loss) Effects of Cash Flow Hedges (Detail) - Cash Flow Hedges - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	$ (108)	$ (106)	$ (266)	$ 39
Gain (loss) reclassified into net income from OCI	52	58	108	119
Gain (loss) recognized in net income (loss)	0	0	0	0
Interest Rate Swaps Hedging Assets \| Net Investment Income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	(77)	(104)	(225)	42
Gain (loss) reclassified into net income from OCI	52	55	105	109
Interest Rate Swaps Hedging Assets \| Gain (Loss) on Investments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	0	0	0	0
Gain (loss) reclassified into net income from OCI	1	3	5	8
Gain (loss) recognized in net income (loss)	0	0	0	0
Interest Rate Swaps Hedging Liabilities \| Interest Expense
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	0		0	0
Gain (loss) reclassified into net income from OCI	(1)		(2)	(1)
Interest Rate Swaps Hedging Liabilities \| Gain (Loss) on Investments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI				0
Gain (loss) reclassified into net income from OCI				1
Gain (loss) recognized in net income (loss)	0		0	0
Foreign currency swaps \| Net Investment Income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	2	(2)	3	(3)
Gain (loss) reclassified into net income from OCI	0	0	0	0
Foreign currency swaps \| Gain (Loss) on Investments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI				0
Gain (loss) reclassified into net income from OCI				2
Gain (loss) recognized in net income (loss)	0	$ 0	0	$ 0
Forward Bond Purchase Commitments \| Gain (Loss) on Investments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	(33)		(44)
Gain (loss) reclassified into net income from OCI	0		0
Gain (loss) recognized in net income (loss)	$ 0		$ 0

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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