INVESTMENTS - Other Investments (Details) - USD ($) $ in Millions		Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Other investments	[1]	$ 7,706	$ 3,402
Transitional real estate loans
Investment [Line Items]
Other investments		4,377	1,235
Commercial mortgage loans
Investment [Line Items]
Other investments		1,064	908
Middle market loans
Investment [Line Items]
Other investments		1,478	859
Policy loans
Investment [Line Items]
Other investments		232	210
Short-term investments
Investment [Line Items]
Other investments		152	57
Other Investments
Investment [Line Items]
Other investments		$ 403	$ 133

[1] Includes $5,856 in 2018 and $2,341 in 2017 of loan receivables and limited partnerships from consolidated variable interest entities