INVESTMENTS - Investments in Consolidated Variable Interest Entities (Detail) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		$ 81,474	$ 76,856
Available for sale, fixed maturity securities		93,940	82,895
Equity securities		830	987
Commercial mortgage and other loans		8,284	6,919
Commercial mortgage and other loans, fair value		8,360	6,893
Other investments		1,507	787
Asset derivatives		411	417
Assets, fair value		100,119	88,788
Liability derivatives		403	387
Liabilities		124,699	116,944
Liabilities, fair value		403	387
Variable Interest Entity, Consolidated
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		3,594	3,849
Available for sale, fixed maturity securities		4,562	4,466
Equity securities, FV-NI, cost		0	160
Equity securities		0	160
Commercial mortgage and other loans		6,813	5,528
Commercial mortgage and other loans, fair value		6,868	5,506
Other investments	[1]	439	328
Other investments, fair value	[1]	439	328
Asset derivatives, amortized cost	[2]	147	182
Asset derivatives	[2]	147	182
Assets, amortized cost		10,993	10,047
Assets, fair value		12,016	10,642
Liability derivatives, amortized cost	[2]	139	102
Liability derivatives	[2]	139	102
Liabilities		139	102
Liabilities, fair value		$ 139	$ 102

[1] Consists entirely of alternative investments in limited partnerships

[2] Consists entirely of derivatives