INVESTMENTS - Information Regarding Changes in Unrealized Gains and Losses from Investments (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)		$ (3,142)	$ 1,728	$ 2,799
Fixed maturity securities | Available-for-sale securities
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)	[1]	(3,142)	1,657	2,711
Equity securities
Changes in unrealized gains (losses):
Changes in unrealized gains (losses)	[2]	$ 0	$ 71	$ 88

[1] Includes perpetual securities

[2] See Note 1 and Note 11 of the Notes to the Consolidated Financial Statements for the adoption of accounting guidance and the cumulative effect of the change in accounting principle related to financial instruments effective January 1, 2018.