INVESTMENTS (MORTGAGE LOANS) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Commercial Mortgage Loans
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	$ 5,375	$ 4,847
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	0	30
Financing receivables, recorded investment, current	5,375	4,817
Total financing receivables	5,375	4,847
Financing receivable, recorded investment, 90 days or more past due and accruing	0	0
Commercial Mortgage Loans \| With No Related Allowance Recorded
Impaired Mortgage Loans [Abstract]
Impaired financing receivable, recorded investment	16	46
Impaired financing receivable, unpaid principal balance	16	46
Related allowance	0	0
Impaired financing receivable, average recorded investment	31	15
Impaired financing receivable, interest income recognized	0	0
Commercial Mortgage Loans \| With Related Allowance Recorded
Impaired Mortgage Loans [Abstract]
Impaired financing receivable, recorded investment	61	63
Impaired financing receivable, unpaid principal balance	61	63
Related allowance	(7)	(6)
Impaired financing receivable, average recorded investment	62	137
Impaired financing receivable, interest income recognized	1	4
Commercial Mortgage Loans \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	2,608	2,129
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	2,608	2,129
Commercial Mortgage Loans \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	487	353
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	487	353
Commercial Mortgage Loans \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,002	1,049
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	1,002	1,049
Commercial Mortgage Loans \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,043	1,045
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	1,043	1,045
Commercial Mortgage Loans \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	189	225
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	189	225
Commercial Mortgage Loans \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	46	46
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	46	46
Commercial Mortgage Loans \| 0% - 50%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	853	671
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	853	671
Commercial Mortgage Loans \| 0% - 50% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	715	533
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	715	533
Commercial Mortgage Loans \| 0% - 50% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	45	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	45	0
Commercial Mortgage Loans \| 0% - 50% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	57	102
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	57	102
Commercial Mortgage Loans \| 0% - 50% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	12	12
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	12	12
Commercial Mortgage Loans \| 0% - 50% \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	24	24
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	24	24
Commercial Mortgage Loans \| 0% - 50% \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Commercial Mortgage Loans \| 50% - 70%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	3,746	3,416
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	3,746	3,416
Commercial Mortgage Loans \| 50% - 70% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,713	1,392
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	1,713	1,392
Commercial Mortgage Loans \| 50% - 70% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	396	353
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	396	353
Commercial Mortgage Loans \| 50% - 70% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	739	741
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	739	741
Commercial Mortgage Loans \| 50% - 70% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	821	853
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	821	853
Commercial Mortgage Loans \| 50% - 70% \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	77	77
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	77	77
Commercial Mortgage Loans \| 50% - 70% \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Commercial Mortgage Loans \| 70% - 90%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	698	651
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	698	651
Commercial Mortgage Loans \| 70% - 90% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	118	141
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	118	141
Commercial Mortgage Loans \| 70% - 90% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	46	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	46	0
Commercial Mortgage Loans \| 70% - 90% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	206	206
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	206	206
Commercial Mortgage Loans \| 70% - 90% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	194	134
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	194	134
Commercial Mortgage Loans \| 70% - 90% \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	88	124
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	88	124
Commercial Mortgage Loans \| 70% - 90% \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	46	46
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	46	46
Commercial Mortgage Loans \| 90% plus
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	78	109
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	78	109
Commercial Mortgage Loans \| 90% plus \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	62	63
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	62	63
Commercial Mortgage Loans \| 90% plus \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Commercial Mortgage Loans \| 90% plus \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Commercial Mortgage Loans \| 90% plus \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	16	46
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	16	46
Commercial Mortgage Loans \| 90% plus \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Commercial Mortgage Loans \| 90% plus \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Commercial Mortgage Loans \| 30 to 59 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	0	0
Commercial Mortgage Loans \| 60 to 89 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	0	0
Commercial Mortgage Loans \| 90 Days or More
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	0	30
Agricultural Mortgage Loans
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	2,328	2,330
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	48	23
Financing receivables, recorded investment, current	2,280	2,307
Total financing receivables	2,328	2,330
Financing receivable, recorded investment, 90 days or more past due and accruing	2	4
Agricultural Mortgage Loans \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	360	350
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	360	350
Agricultural Mortgage Loans \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	200	196
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	200	196
Agricultural Mortgage Loans \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	458	471
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	458	471
Agricultural Mortgage Loans \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	752	734
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	752	734
Agricultural Mortgage Loans \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	472	481
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	472	481
Agricultural Mortgage Loans \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	86	98
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	86	98
Agricultural Mortgage Loans \| 0% - 50%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,340	1,336
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	1,340	1,336
Agricultural Mortgage Loans \| 0% - 50% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	218	204
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	218	204
Agricultural Mortgage Loans \| 0% - 50% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	130	116
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	130	116
Agricultural Mortgage Loans \| 0% - 50% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	269	277
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	269	277
Agricultural Mortgage Loans \| 0% - 50% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	430	432
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	430	432
Agricultural Mortgage Loans \| 0% - 50% \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	248	256
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	248	256
Agricultural Mortgage Loans \| 0% - 50% \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	45	51
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	45	51
Agricultural Mortgage Loans \| 50% - 70%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	982	988
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	982	988
Agricultural Mortgage Loans \| 50% - 70% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	142	146
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	142	146
Agricultural Mortgage Loans \| 50% - 70% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	70	80
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	70	80
Agricultural Mortgage Loans \| 50% - 70% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	187	192
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	187	192
Agricultural Mortgage Loans \| 50% - 70% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	318	298
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	318	298
Agricultural Mortgage Loans \| 50% - 70% \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	224	225
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	224	225
Agricultural Mortgage Loans \| 50% - 70% \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	41	47
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	41	47
Agricultural Mortgage Loans \| 70% - 90%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	6	6
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	6	6
Agricultural Mortgage Loans \| 70% - 90% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 70% - 90% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 70% - 90% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	2	2
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	2	2
Agricultural Mortgage Loans \| 70% - 90% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	4	4
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	4	4
Agricultural Mortgage Loans \| 70% - 90% \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 70% - 90% \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 90% plus
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 90% plus \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 90% plus \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 90% plus \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 90% plus \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 90% plus \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 90% plus \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	0	0
Agricultural Mortgage Loans \| 30 to 59 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	2	12
Agricultural Mortgage Loans \| 60 to 89 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	44	7
Agricultural Mortgage Loans \| 90 Days or More
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	2	4
Total Mortgages Loan
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	7,703	7,177
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing receivables, recorded investment, past due	48	53
Financing receivables, recorded investment, current	7,655	7,124
Total financing receivables	7,703	7,177
Financing receivable, recorded investment, 90 days or more past due and accruing	2	4
Total Mortgages Loan \| With No Related Allowance Recorded
Impaired Mortgage Loans [Abstract]
Impaired financing receivable, recorded investment	16	46
Impaired financing receivable, unpaid principal balance	16	46
Related allowance	0	0
Impaired financing receivable, average recorded investment	31	15
Impaired financing receivable, interest income recognized	0	0
Total Mortgages Loan \| With Related Allowance Recorded
Impaired Mortgage Loans [Abstract]
Impaired financing receivable, recorded investment	61	63
Impaired financing receivable, unpaid principal balance	61	63
Related allowance	(7)	(6)
Impaired financing receivable, average recorded investment	62	137
Impaired financing receivable, interest income recognized	1	4
Total Mortgages Loan \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	2,968	2,479
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	2,968	2,479
Total Mortgages Loan \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	687	549
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	687	549
Total Mortgages Loan \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,460	1,520
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	1,460	1,520
Total Mortgages Loan \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,795	1,779
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	1,795	1,779
Total Mortgages Loan \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	661	706
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	661	706
Total Mortgages Loan \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	132	144
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	132	144
Total Mortgages Loan \| 0% - 50%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	2,193	2,007
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	2,193	2,007
Total Mortgages Loan \| 0% - 50% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	933	737
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	933	737
Total Mortgages Loan \| 0% - 50% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	175	116
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	175	116
Total Mortgages Loan \| 0% - 50% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	326	379
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	326	379
Total Mortgages Loan \| 0% - 50% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	442	444
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	442	444
Total Mortgages Loan \| 0% - 50% \| 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	272	280
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	272	280
Total Mortgages Loan \| 0% - 50% \| Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	45	51
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	45	51
Total Mortgages Loan \| 50% - 70%
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	4,728	4,404
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	4,728	4,404
Total Mortgages Loan \| 50% - 70% \| Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,855	1,538
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	1,855	1,538
Total Mortgages Loan \| 50% - 70% \| 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	466	433
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	466	433
Total Mortgages Loan \| 50% - 70% \| 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	926	933
Financing Receivable, Recorded Investment, Aging [Abstract]
Total financing receivables	926	933
Total Mortgages Loan \| 50% - 70% \| 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Mortgage loans on real estate	1,139	1,151
Financing Receivable, Recorded Investment, Aging [Abstract]

INVESTMENTS (MORTGAGE LOANS) (Details) - USD ($)
$ in Millions

3 Months Ended

12 Months Ended

Mar. 31, 2016

Dec. 31, 2015

Commercial Mortgage Loans

Mortgage Loans on Real Estate [Line Items]

Mortgage loans on real estate

$ 5,375

$ 4,847

Financing Receivable, Recorded Investment, Aging [Abstract]

Financing receivables, recorded investment, past due