SIGNIFICANT ACCOUNTING POLICIES - Variable Interest Entities (Details) $ in Millions		3 Months Ended
		Mar. 31, 2020 USD ($) joint_venture	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) joint_venture
Variable Interest Entity [Line Items]
Assets		$ 240,781		$ 249,870
Liabilities		218,884		234,379
Redeemable non-controlling interest	[1],[2]	$ 257		$ 365
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Number of consolidated real estate joint ventures | joint_venture		1		1
Assets		$ 32		$ 32
Number of nonconsolidated real estate joint ventures | joint_venture		1
Operating income (loss)		$ (5)	$ (5)
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Assets		1,200		1,200
Variable interest entity, nonconsolidated net assets		151,400		160,200
Variable interest entity, maximum loss exposure		1,200		1,200
Variable interest entity, unfunded commitments		1,100		1,100
AB-Sponsored Investment Funds
Variable Interest Entity [Line Items]
Variable interest entity, nonconsolidated net assets		80,500		79,300
Variable interest entity, maximum loss exposure		7		8
AB-Sponsored Investment Funds | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Assets		377		424
Liabilities		73		12
Redeemable non-controlling interest		179		273
AB-Sponsored Investment Funds | VOE Consolidation Model
Variable Interest Entity [Line Items]
Assets		193		188
Liabilities		32		19
Redeemable non-controlling interest		$ 46		$ 52

[1] See Note 13 for details of Redeemable noncontrolling interest.

[2] See Note 2 for details of balances with variable interest entities.