Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Intangible assets	$ 330		$ 330		$ 362
Amortization of intangible assets	13	$ 14	28	$ 33
2019	17		17
2020	31		31
2021	29		29
2022	26		26
2023	24		24
Thereafter	190		190
Finite-Lived Intangible Assets, Net	316		316		353
PWIC
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	14		14		9
Insurance Intangible Asset [Member]
Intangible Assets, Gross (Excluding Goodwill)	1,249		1,249		1,278
Finite-Lived Intangible Assets, Accumulated Amortization	965		965		958
Intangible assets	284		284		320
Amortization of intangible assets	13	13	26	31
2019	15		15
2020	28		28
2021	26		26
2022	24		24
2023	22		22
Thereafter	170		$ 170
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			7 years 3 months 18 days
Other Intangible Assets
Intangible Assets, Gross (Excluding Goodwill)	36		$ 36		36
Finite-Lived Intangible Assets, Accumulated Amortization	4		4		3
Intangible assets	32		32		$ 33
Amortization of intangible assets	1	$ 1	1	$ 1
2019	1		1
2020	3		3
2021	3		3
2022	3		3
2023	2		2
Thereafter	$ 20		$ 20
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			5 years 9 months 18 days

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after 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 remainder of current fiscal year.

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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 fourth 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 before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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