Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Insurance losses and contract holders' benefits	$ 1,086	$ 936	$ 2,089	$ 1,796
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	98	86	183	169
Ceded earned premiums	(19)	(19)	(37)	(36)
Earned premiums	79	67	146	133
Direct contract holders' benefits incurred	100	87	185	172
Ceded contract holders' benefits incurred	(21)	(14)	(33)	(29)
Insurance losses and contract holders' benefits	$ 79	$ 73	$ 152	$ 143

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Amount of earned premiums ceded to other entities.

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