FAIR VALUE MEASUREMENTS - Changes in Available-For-Sale Investments and Derivatives Classified as Level 3 (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		$ 295	$ 205	$ 223	$ 58
Realized investment gains (losses) included in earnings		(10)	122	28	268
Unrealized gains (losses) included in other comprehensive income (loss)		1	25	8	31
Purchases		87	0	124	0
Issuances		0	0	0	0
Sales		0	0	(1)	0
Settlements		(7)	(11)	(16)	(16)
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	0
Balance, end of period		366	341	366	341
Change in unrealized gains (losses) still held		(10)	122	28	268
Foreign currency swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	[1]	19	(63)	(21)	(192)
Realized gains or losses included in earnings	[1]	(10)	123	28	268
Unrealized gains or losses included in other comprehensive income (loss)	[1]	(2)	(1)	0	(16)
Purchases	[1]	0	0	0	0
Issuances	[1]	0	0	0	0
Sales	[1]	0	0	0	0
Settlements	[1]	0	0	0	(1)
Transfers into Level 3	[1]	0	0	0	0
Transfers out of Level 3	[1]	0	0	0	0
Balance, end of period	[1]	7	59	7	59
Changes in unrealized gain (losses) still held	[1]	(10)	123	28	268
Credit default swaps
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	[1]	2	2	2	1
Realized gains or losses included in earnings	[1]	0	(1)	0	0
Unrealized gains or losses included in other comprehensive income (loss)	[1]	0	0	0	0
Purchases	[1]	0	0	0	0
Issuances	[1]	0	0	0	0
Sales	[1]	0	0	0	0
Settlements	[1]	0	0	0	0
Transfers into Level 3	[1]	0	0	0	0
Transfers out of Level 3	[1]	0	0	0	0
Balance, end of period	[1]	2	1	2	1
Changes in unrealized gain (losses) still held	[1]	0	(1)	0	0
Fixed maturities | Mortgage- and asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		195	237	198	220
Realized investment gains (losses) included in earnings		0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)		0	26	6	47
Purchases		0	0	0	0
Issuances		0	0	0	0
Sales		0	0	0	0
Settlements		(7)	(11)	(16)	(15)
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	0
Balance, end of period		188	252	188	252
Change in unrealized gains (losses) still held		0	0	0	0
Fixed maturities | Public utilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		16	0	16	0
Realized investment gains (losses) included in earnings		0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)		0	0	0	0
Purchases		37	0	37	0
Issuances		0	0	0	0
Sales		0	0	0	0
Settlements		0	0	0	0
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	0
Balance, end of period		53	0	53	0
Change in unrealized gains (losses) still held		0	0	0	0
Fixed maturities | Banks/financial institutions
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		24	26	25	26
Realized investment gains (losses) included in earnings		0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)		1	0	0	0
Purchases		0	0	0	0
Issuances		0	0	0	0
Sales		0	0	0	0
Settlements		0	0	0	0
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	0
Balance, end of period		25	26	25	26
Change in unrealized gains (losses) still held		0	0	0	0
Fixed maturities | Other corporate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		35	0	0	0
Realized investment gains (losses) included in earnings		0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)		2	0	2	0
Purchases		40	0	75	0
Issuances		0	0	0	0
Sales		0	0	0	0
Settlements		0	0	0	0
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	0
Balance, end of period		77	0	77	0
Change in unrealized gains (losses) still held		0	0	0	0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period		4	3	3	3
Realized investment gains (losses) included in earnings		0	0	0	0
Unrealized gains (losses) included in other comprehensive income (loss)		0	0	0	0
Purchases		10	0	12	0
Issuances		0	0	0	0
Sales		0	0	(1)	0
Settlements		0	0	0	0
Transfers into Level 3		0	0	0	0
Transfers out of Level 3		0	0	0	0
Balance, end of period		14	3	14	3
Change in unrealized gains (losses) still held		$ 0	$ 0	$ 0	$ 0

[1] Derivative assets and liabilities are presented net