Reinsurance - Life Insurance Ceded Business (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Insurance losses and contract holders' benefits	$ 936	$ 883	$ 1,796	$ 1,737
Life Insurance Segment
Reinsurance for Insurance Companies, by Product Segment [Line Items]
Direct earned premiums	86	81	169	158
Ceded earned premiums	(19)	(17)	(36)	(34)
Earned premiums	67	64	133	124
Direct contract holders' benefits incurred	87	70	172	146
Ceded contract holders' benefits incurred	(14)	(8)	(29)	(21)
Insurance losses and contract holders' benefits	$ 73	$ 62	$ 143	$ 125

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Amount of earned premiums ceded to other entities.

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