Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reinsurance for Insurance Companies, by Product Segment
Insurance losses and contract holders' benefits	$ 1,072	$ 1,143	$ 2,990	$ 3,232
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment
Direct earned premiums	93	90	278	273
Ceded earned premiums	(20)	(18)	(57)	(55)
Earned premiums	73	72	221	218
Direct contract holders' benefits incurred	103	85	310	270
Ceded contract holders' benefits incurred	(19)	(13)	(61)	(46)
Insurance losses and contract holders' benefits	$ 84	$ 72	$ 249	$ 224

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Amount of earned premiums ceded to other entities.

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