Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Insurance losses and contract holders' benefits	$ 932	$ 879	$ 2,728	$ 2,616
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	87	79	256	237
Ceded earned premiums	(17)	(18)	(53)	(52)
Earned premiums	70	61	203	185
Direct contract holders' benefits incurred	87	82	259	228
Ceded contract holders' benefits incurred	(19)	(16)	(48)	(37)
Insurance losses and contract holders' benefits	$ 68	$ 66	$ 211	$ 191

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Amount of earned premiums ceded to other entities.

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