Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Insurance losses and contract holders' benefits	$ 1,143	$ 932	$ 3,232	$ 2,728
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	90	87	273	256
Ceded earned premiums	(18)	(17)	(55)	(53)
Earned premiums	72	70	218	203
Direct contract holders' benefits incurred	85	87	270	259
Ceded contract holders' benefits incurred	(13)	(19)	(46)	(48)
Insurance losses and contract holders' benefits	$ 72	$ 68	$ 224	$ 211

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Amount of earned premiums ceded to other entities.

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