INVESTMENTS - Investments in Variable Interest Entities Not Consolidated (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		$ 87,881	$ 79,371
Available for sale, fixed maturity securities		96,288	91,262
Securities held to maturity, fixed maturities, amortized cost		23,287	30,085
Held to maturity, fixed maturity securities, fair value		29,347	37,594
Other investments		1,843	1,477
Assets, fair value		102,460	98,070
Variable Interest Entity, Not Consolidated
Variable Interest Entity [Line Items]
Available for sale, fixed maturity securities, amortized cost		5,999	4,129
Available for sale, fixed maturity securities		6,397	4,884
Securities held to maturity, fixed maturities, amortized cost		0	1,848
Held to maturity, fixed maturity securities, fair value		0	2,236
Other investments	[1]	119	75
Other investments, fair value	[1]	119	74
Assets, amortized cost		6,118	6,052
Assets, fair value		$ 6,516	$ 7,194

[1] Consists entirely of alternative investments in limited partnerships