Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Reinsurance for Insurance Companies, by Product Segment
Insurance losses and contract holders' benefits	$ 915	$ 1,086	$ 1,918	$ 2,089
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment
Direct earned premiums	98	98	185	183
Ceded earned premiums	(19)	(19)	(37)	(37)
Earned premiums	79	79	148	146
Direct contract holders' benefits incurred	100	100	207	185
Ceded contract holders' benefits incurred	(15)	(21)	(42)	(33)
Insurance losses and contract holders' benefits	$ 85	$ 79	$ 165	$ 152

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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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