SIGNIFICANT ACCOUNTING POLICIES SIGNIFICANT ACCOUTNING POLICIES – Schedule of Accounting Change Adjustments made to the Consolidated Statements of Comprehensive income (loss) (Details) - USD ($) $ in Millions	3 Months Ended						6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other operating costs and expenses	$ 449			$ 319					$ 992	$ 1,070
Interest credited to policyholders’ account balances	350			303					1,008	779
Net income (loss)	66	$ 1,714	$ (120)	137	$ 576	$ 1,067	$ 1,593	$ 1,642	1,677	1,779	$ 524	$ 1,070	$ 3,100
Change in unrealized gains (losses), net of reclassification adjustment	(55)	315	108	16	610	717	423	1,327	362	1,342	(180)	(831)	891
Other comprehensive income (loss)	(52)	295	143	15	605	726	438	1,331	380	1,345	(201)	(860)	847
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	14	2,009	23	152	1,181	1,793	2,031	2,973	2,057	3,124	323	210	3,947
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	154			127					372	335
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ (140)	1,916	(102)	25	1,093	1,673	2,031	2,765	1,685	2,789	(156)	(178)	3,589
As Revised
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other operating costs and expenses											1,458	1,497	1,668
Interest credited to policyholders’ account balances			336	303	255	221	658	476		779	1,082	976	1,037
Increase Decrease In Fair Value Of Reinsurance Contracts			0			0
Net income (loss)		1,450	(312)	33	1,040	1,736	1,137	2,776		2,809	430	1,475	4,281
Change in unrealized gains (losses), net of reclassification adjustment		314	144	8	610	786	458	1,396		1,403	(197)	(901)	969
Other comprehensive income (loss)		294	179	7	605	795	473	1,400		1,406	(218)	(930)	925
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest		1,744	(133)	40	1,645	2,531	1,610	4,176		4,215	212	545	5,206
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest			125	127	88	120		208		335	479	388	358
Comprehensive Income (Loss), Net of Tax, Attributable to Parent		1,651	(258)	(87)	1,557	2,411	1,610	3,968		3,880	(267)	157	4,848
Impact of Revision
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net income (loss)		264	192	104	(464)	(669)	456	(1,134)		(1,030)	94	(405)	(1,181)
Change in unrealized gains (losses), net of reclassification adjustment		1	(36)	8	0	(69)	(35)	(69)		(61)	17	70	(78)
Other comprehensive income (loss)		1	(36)	8	0	(69)	(35)	(69)		(61)	17	70	(78)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest		265	156	112	(464)	(738)	421	(1,203)		(1,091)	111	(335)	(1,259)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent		265	156	0	(464)	(738)	421	(1,203)		0	111	(335)	(1,259)
As previously reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other operating costs and expenses											1,458	1,415	1,692
Interest credited to policyholders’ account balances			337	272	274	251	658	525		797	981	1,048	1,155
Increase Decrease In Fair Value Of Reinsurance Contracts			0			0
Net income (loss)		1,459	(313)	22	1,061	1,720	1,146	2,781		2,803	544	1,464	4,420
Change in unrealized gains (losses), net of reclassification adjustment			144	(22)	625	780		1,405		1,383	(217)	(881)	969
Other comprehensive income (loss)			179	(23)	620	789		1,409		1,386	(238)	(910)	925
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest		1,753	(134)	(1)	1,681	2,509	1,619	4,190		4,189	306	554	5,345
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest			125	99	89	120		209		308	452	388	358
Comprehensive Income (Loss), Net of Tax, Attributable to Parent		$ 1,660	(259)	$ (100)	$ 1,592	2,389	1,619	3,981		3,881	(146)	166	4,987
AOCI Attributable to Parent
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other comprehensive income (loss)			136			723	451	1,331	$ 361	1,344	(184)	(845)	876
AOCI Attributable to Parent | As Revised
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other comprehensive income (loss)			172			792	486	1,400		1,405	(201)	(915)	954
AOCI Attributable to Parent | Impact of Revision
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other comprehensive income (loss)			(36)			(69)	(35)	(69)		(61)	17	70	(78)
AOCI Attributable to Parent | As previously reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other comprehensive income (loss)			$ 172			$ 786	$ 486	$ 1,409		$ 1,385	$ (221)	$ (895)	$ 954