REVISION OF PRIOR PERIOD FINANCIAL STATEMENTS - Equity (Details) - USD ($) $ in Millions	3 Months Ended						6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 15,088	$ 18,798	$ 11,565	$ 13,781	$ 12,281	$ 12,359	$ 11,565	$ 12,359	$ 11,565	$ 12,359	$ 12,359	$ 19,395
Net income (loss) attributable to Equitable Financial	(946)	(4,090)	5,757	(264)	267	(851)	1,667	(584)	721	(848)	(1,889)	(899)	$ 2,790
Other comprehensive income (loss)	247	1,570	1,510	730	1,226	765	3,080	1,991	3,327	2,721	2,097	(1,225)	582
Ending balance	14,399	15,088	18,798	13,254	13,781	12,281	15,088	13,781	14,399	13,254	11,565	12,359	19,395
As Previously Reported
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	15,166	18,881	11,658	13,932	12,370	12,428	11,658	12,428	11,658	12,428	12,428	19,492
Net income (loss) attributable to Equitable Financial		(4,095)	5,743	(262)	264	(830)	1,648	(566)		(828)	(1,851)	(918)	2,843
Other comprehensive income (loss)		1,570	1,514	574	1,291	764	3,084	2,055		2,629	2,083	(1,234)	602
Ending balance		15,166	18,881	13,251	13,932	12,370	15,166	13,932		13,251	11,658	12,428	19,492
Impact of Revisions
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(78)	(83)	(93)	(151)	(89)	(69)	(93)	(69)	(93)	(69)	(69)	(97)
Net income (loss) attributable to Equitable Financial		5	14	(2)	3	(21)	19	(18)		(20)	(38)	19	(53)
Other comprehensive income (loss)		0	(4)	156	(65)	1	(4)	(64)		92	14	9	(20)
Ending balance		(78)	(83)	3	(151)	(89)	(78)	(151)		3	(93)	(69)	(97)
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	2,580	7,870	2,145	4,455	4,188	5,039	2,145	5,039	2,145	5,039	5,039	8,860	6,070
Net income (loss) attributable to Equitable Financial		(4,090)	5,757	(264)	267	(851)	1,667	(584)		(848)	(1,889)	(899)	2,790
Ending balance	1,634	2,580	7,870	3,191	4,455	4,188	2,580	4,455	1,634	3,191	2,145	5,039	8,860
Retained Earnings | As Previously Reported
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	2,658	7,953	2,242	4,532	4,268	5,098	2,242	5,098	2,242	5,098	5,098	8,938	6,095
Net income (loss) attributable to Equitable Financial		(4,095)	5,743	(262)	264	(830)	1,648	(566)		(828)	(1,851)	(918)	2,843
Ending balance		2,658	7,953	3,270	4,532	4,268	2,658	4,532		3,270	2,242	5,098	8,938
Retained Earnings | Impact of Revisions
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(78)	(83)	(97)	(77)	(80)	(59)	(97)	(59)	(97)	(59)	(59)	(78)	(25)
Net income (loss) attributable to Equitable Financial		5	14	(2)	3	(21)	19	(18)		(20)	(38)	19	(53)
Ending balance		(78)	(83)	(79)	(77)	(80)	(78)	(77)		(79)	(97)	(59)	(78)
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	4,676	3,106	1,596	1,490	264	(501)	1,596	(501)	1,596	(501)	(501)	579	(3)
Other comprehensive income (loss)	247			730	1,226	765		1,991	3,327	2,721	2,097	(1,225)	582
Ending balance	4,923	4,676	3,106	2,220	1,490	264	4,676	1,490	4,923	2,220	1,596	(501)	579
Accumulated Other Comprehensive Income (Loss) | As Previously Reported
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		3,106	1,592	1,564	273	(491)	1,592	(491)	1,592	(491)	(491)	598	(4)
Other comprehensive income (loss)				574	1,291	764		2,055		2,629	2,083	(1,234)	602
Ending balance			3,106	2,138	1,564	273		1,564		2,138	1,592	(491)	598
Accumulated Other Comprehensive Income (Loss) | Impact of Revisions
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance		0	4	(74)	(9)	(10)	4	(10)	4	(10)	(10)	(19)	1
Other comprehensive income (loss)				156	(65)	1		(64)		92	14	9	(20)
Ending balance			0	82	(74)	(9)		(74)		82	4	(10)	(19)
Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	15,079	18,789	11,552	13,769	12,269	12,347	11,552	12,347	11,552	12,347	12,347	16,300
Other comprehensive income (loss)	247			730					3,327	2,721
Ending balance	14,390	15,079	18,789	13,242	13,769	12,269	15,079	13,769	14,390	13,242	11,552	12,347	16,300
Parent | As Previously Reported
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	15,157	18,872	11,645	13,920	12,358	12,416	11,645	12,416	11,645	12,416	12,416	16,397
Ending balance		15,157	18,872	13,239	13,920	12,358	15,157	13,920		13,239	11,645	12,416	16,397
Parent | Impact of Revisions
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ (78)	(83)	(93)	(151)	(89)	(69)	(93)	(69)	$ (93)	(69)	(69)	(97)
Ending balance		$ (78)	$ (83)	$ 3	$ (151)	$ (89)	$ (78)	$ (151)		$ 3	$ (93)	$ (69)	$ (97)