Other Intangible Assets - Summary of Changes in Carrying Amounts of Intangible Assets Including DAC, VOBA , and DSI (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Total
Balance at beginning of period	$ 2,034	$ 1,724
Purchase price allocation adjustments	0	61
Deferrals	814	675
Amortization	(353)	(517)
Interest	57	44
Unlocking	(4)	12
Adjustment for net unrealized investment (losses) gains	912	35
Balance at end of period	3,460	2,034
VOBA
Total
Balance at beginning of period	1,185	1,466
Purchase price allocation adjustments		61
Deferrals	0	0
Amortization	(203)	(436)
Interest	25	30
Unlocking	(5)	13
Adjustment for net unrealized investment (losses) gains	662	51
Balance at end of period	1,664	1,185
DAC
Total
Balance at beginning of period	761	222
Purchase price allocation adjustments	0	0
Deferrals	727	585
Amortization	(107)	(46)
Interest	30	13
Unlocking	(4)	1
Adjustment for net unrealized investment (losses) gains	182	(14)
Balance at end of period	1,589	761
DSI
Total
Balance at beginning of period	88	36
Purchase price allocation adjustments	0	0
Deferrals	87	90
Amortization	(43)	(35)
Interest	2	1
Unlocking	5	(2)
Adjustment for net unrealized investment (losses) gains	68	(2)
Balance at end of period	$ 207	$ 88

Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Purchase Price Allocation Adjustments

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Deferred Policy Acquisition Costs and Present Value of Future Profits, Unlocking Adjustment

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Amount of amortization expense for deferred policy acquisition costs and present value of future profits from insurance contract acquired in business combination, from accrued interest on unamortized balance.

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Amount of unrealized investment gain (loss) which decreases (increases) deferred policy acquisition costs and present value of future profits from insurance contract acquired in business combination.

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Amount of addition in deferred policy acquisition costs and present value of future profits from insurance contract acquired in business combination.

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Amount of amortization expense (reversal of expense) for deferred policy acquisition costs and present value of future profits from insurance contract acquired in business combination.

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Amount, after accumulated amortization, of deferred policy acquisition costs and present value of future profits from insurance contract acquired in business combination.

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