Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Reinsurance for Insurance Companies, by Product Segment
Insurance losses and contract holders' benefits	$ 1,003	$ 1,003
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment
Direct earned premiums	87	85
Ceded earned premiums	(18)	(18)
Earned premiums	69	67
Direct contract holders' benefits incurred	107	85
Ceded contract holders' benefits incurred	(27)	(12)
Insurance losses and contract holders' benefits	$ 80	$ 73

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Amount of earned premiums ceded to other entities.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of life premiums earned.

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