Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
VOBA amortization	$ 160	$ 169	$ 180
VOBA amortization including adjustment	175
DAC amortization	(280)	(186)	(99)
DIS Amortization	(40)	(22)	(14)
Amortization of intangible assets	187	152	134
Expected amortization, 2025	172
Expected amortization, 2026	140
Expected amortization, 2027	112
Expected amortization, 2028	85
Expected amortization, 2029	72
Finite-Lived Intangible Assets [Line Items]
Definite lived	966	620
Depreciation and amortization	739	593	491
Trademarks, Tradenames and Other/Market Risk Benefit Offset
Finite-Lived Intangible Assets [Line Items]
Definite lived	94	22
Depreciation and amortization	$ 5	$ 1	$ 1

Present Value of Future Insurance Profits, Amortization Expense, Including Experience Adjustment Amortization Expense

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense (reversal of expense) for present value of future profits of insurance contract acquired in business combination.

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