INVESTMENTS (LOANS) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Agricultural Mortgages
Mortgage Loans on Real Estate [Line Items]
Financing Receivable, Allowance for Credit Losses	$ 0	$ 0	$ 0
Commercial Real Estate Portfolio Segment
Mortgage Loans on Real Estate [Line Items]
Financing Receivable, Allowance for Credit Losses	8,000,000	8,000,000	$ 6,000,000	$ 37,000,000
Face amount of mortgage loans	8,369,000,000	7,264,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	27,000,000	0
Current	8,342,000,000	7,264,000,000
Total Financing Receivables	8,369,000,000	7,264,000,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	0	0
Commercial Real Estate Portfolio Segment | With no related allowance recorded
Impaired Mortgage Loans [Abstract]
Recorded Investment	0	15,000,000
Unpaid Principal Balance	0	15,000,000
Related Allowance	0	0
Average Recorded Investment	0	22,000,000
Interest Income Recognized	0	0
Commercial Real Estate Portfolio Segment | With related allowance recorded
Impaired Mortgage Loans [Abstract]
Recorded Investment	27,000,000	27,000,000
Unpaid Principal Balance	27,000,000	27,000,000
Related Allowance	(8,000,000)	(8,000,000)
Average Recorded Investment	27,000,000	48,000,000
Interest Income Recognized	2,000,000	2,000,000
Commercial Real Estate Portfolio Segment | 30-59 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	27,000,000	0
Commercial Real Estate Portfolio Segment | 60-89 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	0	0
Commercial Real Estate Portfolio Segment | 90 Days Or Greater
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	0	0
Commercial Real Estate Portfolio Segment | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	4,999,000,000	4,237,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	4,999,000,000	4,237,000,000
Commercial Real Estate Portfolio Segment | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	792,000,000	590,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	792,000,000	590,000,000
Commercial Real Estate Portfolio Segment | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,609,000,000	989,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,609,000,000	989,000,000
Commercial Real Estate Portfolio Segment | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	774,000,000	1,298,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	774,000,000	1,298,000,000
Commercial Real Estate Portfolio Segment | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	195,000,000	104,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	195,000,000	104,000,000
Commercial Real Estate Portfolio Segment | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	46,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	46,000,000
Commercial Real Estate Portfolio Segment | 0% - 50%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,136,000,000	948,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,136,000,000	948,000,000
Commercial Real Estate Portfolio Segment | 0% - 50% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	742,000,000	738,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	742,000,000	738,000,000
Commercial Real Estate Portfolio Segment | 0% - 50% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	95,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	95,000,000
Commercial Real Estate Portfolio Segment | 0% - 50% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	320,000,000	59,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	320,000,000	59,000,000
Commercial Real Estate Portfolio Segment | 0% - 50% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	74,000,000	56,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	74,000,000	56,000,000
Commercial Real Estate Portfolio Segment | 0% - 50% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Commercial Real Estate Portfolio Segment | 0% - 50% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Commercial Real Estate Portfolio Segment | 50% - 70%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	6,409,000,000	5,496,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	6,409,000,000	5,496,000,000
Commercial Real Estate Portfolio Segment | 50% - 70% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	4,088,000,000	3,217,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	4,088,000,000	3,217,000,000
Commercial Real Estate Portfolio Segment | 50% - 70% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	682,000,000	430,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	682,000,000	430,000,000
Commercial Real Estate Portfolio Segment | 50% - 70% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,066,000,000	673,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,066,000,000	673,000,000
Commercial Real Estate Portfolio Segment | 50% - 70% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	428,000,000	1,100,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	428,000,000	1,100,000,000
Commercial Real Estate Portfolio Segment | 50% - 70% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	145,000,000	76,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	145,000,000	76,000,000
Commercial Real Estate Portfolio Segment | 50% - 70% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Commercial Real Estate Portfolio Segment | 70% - 90%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	797,000,000	777,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	797,000,000	777,000,000
Commercial Real Estate Portfolio Segment | 70% - 90% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	169,000,000	282,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	169,000,000	282,000,000
Commercial Real Estate Portfolio Segment | 70% - 90% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	110,000,000	65,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	110,000,000	65,000,000
Commercial Real Estate Portfolio Segment | 70% - 90% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	196,000,000	229,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	196,000,000	229,000,000
Commercial Real Estate Portfolio Segment | 70% - 90% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	272,000,000	127,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	272,000,000	127,000,000
Commercial Real Estate Portfolio Segment | 70% - 90% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	50,000,000	28,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	50,000,000	28,000,000
Commercial Real Estate Portfolio Segment | 70% - 90% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	46,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	46,000,000
Commercial Real Estate Portfolio Segment | 90% plus
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	27,000,000	43,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	27,000,000	43,000,000
Commercial Real Estate Portfolio Segment | 90% plus | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Commercial Real Estate Portfolio Segment | 90% plus | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Commercial Real Estate Portfolio Segment | 90% plus | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	27,000,000	28,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	27,000,000	28,000,000
Commercial Real Estate Portfolio Segment | 90% plus | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	15,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	15,000,000
Commercial Real Estate Portfolio Segment | 90% plus | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Commercial Real Estate Portfolio Segment | 90% plus | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	2,574,000,000	2,501,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	74,000,000	17,000,000
Current	2,500,000,000	2,484,000,000
Total Financing Receivables	2,574,000,000	2,501,000,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	22,000,000	6,000,000
Agricultural Real Estate Portfolio Segment | With no related allowance recorded
Impaired Mortgage Loans [Abstract]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Agricultural Real Estate Portfolio Segment | With related allowance recorded
Impaired Mortgage Loans [Abstract]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Agricultural Real Estate Portfolio Segment | 30-59 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	49,000,000	9,000,000
Agricultural Real Estate Portfolio Segment | 60-89 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	3,000,000	2,000,000
Agricultural Real Estate Portfolio Segment | 90 Days Or Greater
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	22,000,000	6,000,000
Agricultural Real Estate Portfolio Segment | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	383,000,000	395,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	383,000,000	395,000,000
Agricultural Real Estate Portfolio Segment | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	195,000,000	195,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	195,000,000	195,000,000
Agricultural Real Estate Portfolio Segment | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	502,000,000	507,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	502,000,000	507,000,000
Agricultural Real Estate Portfolio Segment | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	878,000,000	805,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	878,000,000	805,000,000
Agricultural Real Estate Portfolio Segment | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	537,000,000	505,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	537,000,000	505,000,000
Agricultural Real Estate Portfolio Segment | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	79,000,000	94,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	79,000,000	94,000,000
Agricultural Real Estate Portfolio Segment | 0% - 50%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,557,000,000	1,491,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,557,000,000	1,491,000,000
Agricultural Real Estate Portfolio Segment | 0% - 50% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	272,000,000	254,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	272,000,000	254,000,000
Agricultural Real Estate Portfolio Segment | 0% - 50% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	149,000,000	138,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	149,000,000	138,000,000
Agricultural Real Estate Portfolio Segment | 0% - 50% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	275,000,000	296,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	275,000,000	296,000,000
Agricultural Real Estate Portfolio Segment | 0% - 50% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	515,000,000	468,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	515,000,000	468,000,000
Agricultural Real Estate Portfolio Segment | 0% - 50% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	316,000,000	286,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	316,000,000	286,000,000
Agricultural Real Estate Portfolio Segment | 0% - 50% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	30,000,000	49,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	30,000,000	49,000,000
Agricultural Real Estate Portfolio Segment | 50% - 70%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,013,000,000	1,004,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,013,000,000	1,004,000,000
Agricultural Real Estate Portfolio Segment | 50% - 70% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	111,000,000	141,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	111,000,000	141,000,000
Agricultural Real Estate Portfolio Segment | 50% - 70% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	46,000,000	57,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	46,000,000	57,000,000
Agricultural Real Estate Portfolio Segment | 50% - 70% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	227,000,000	209,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	227,000,000	209,000,000
Agricultural Real Estate Portfolio Segment | 50% - 70% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	359,000,000	333,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	359,000,000	333,000,000
Agricultural Real Estate Portfolio Segment | 50% - 70% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	221,000,000	219,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	221,000,000	219,000,000
Agricultural Real Estate Portfolio Segment | 50% - 70% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	49,000,000	45,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	49,000,000	45,000,000
Agricultural Real Estate Portfolio Segment | 70% - 90%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	4,000,000	6,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	4,000,000	6,000,000
Agricultural Real Estate Portfolio Segment | 70% - 90% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 70% - 90% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 70% - 90% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	2,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	2,000,000
Agricultural Real Estate Portfolio Segment | 70% - 90% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	4,000,000	4,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	4,000,000	4,000,000
Agricultural Real Estate Portfolio Segment | 70% - 90% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 70% - 90% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 90% plus
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 90% plus | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 90% plus | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 90% plus | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 90% plus | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 90% plus | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Agricultural Real Estate Portfolio Segment | 90% plus | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Total Mortgages Loan
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	10,943,000,000	9,765,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	101,000,000	17,000,000
Current	10,842,000,000	9,748,000,000
Total Financing Receivables	10,943,000,000	9,765,000,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	22,000,000	6,000,000
Total Mortgages Loan | With no related allowance recorded
Impaired Mortgage Loans [Abstract]
Recorded Investment	0	15,000,000
Unpaid Principal Balance	0	15,000,000
Related Allowance	0	0
Average Recorded Investment	0	22,000,000
Interest Income Recognized	0	0
Total Mortgages Loan | With related allowance recorded
Impaired Mortgage Loans [Abstract]
Recorded Investment	27,000,000	27,000,000
Unpaid Principal Balance	27,000,000	27,000,000
Related Allowance	(8,000,000)	(8,000,000)
Average Recorded Investment	27,000,000	48,000,000
Interest Income Recognized	2,000,000	2,000,000
Total Mortgages Loan | 30-59 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	76,000,000	9,000,000
Total Mortgages Loan | 60-89 Days
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	3,000,000	2,000,000
Total Mortgages Loan | 90 Days Or Greater
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Past Due	22,000,000	6,000,000
Total Mortgages Loan | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	5,382,000,000	4,632,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	5,382,000,000	4,632,000,000
Total Mortgages Loan | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	987,000,000	785,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	987,000,000	785,000,000
Total Mortgages Loan | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	2,111,000,000	1,496,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	2,111,000,000	1,496,000,000
Total Mortgages Loan | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,652,000,000	2,103,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,652,000,000	2,103,000,000
Total Mortgages Loan | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	732,000,000	609,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	732,000,000	609,000,000
Total Mortgages Loan | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	79,000,000	140,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	79,000,000	140,000,000
Total Mortgages Loan | 0% - 50%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	2,693,000,000	2,439,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	2,693,000,000	2,439,000,000
Total Mortgages Loan | 0% - 50% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,014,000,000	992,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,014,000,000	992,000,000
Total Mortgages Loan | 0% - 50% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	149,000,000	233,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	149,000,000	233,000,000
Total Mortgages Loan | 0% - 50% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	595,000,000	355,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	595,000,000	355,000,000
Total Mortgages Loan | 0% - 50% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	589,000,000	524,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	589,000,000	524,000,000
Total Mortgages Loan | 0% - 50% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	316,000,000	286,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	316,000,000	286,000,000
Total Mortgages Loan | 0% - 50% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	30,000,000	49,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	30,000,000	49,000,000
Total Mortgages Loan | 50% - 70%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	7,422,000,000	6,500,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	7,422,000,000	6,500,000,000
Total Mortgages Loan | 50% - 70% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	4,199,000,000	3,358,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	4,199,000,000	3,358,000,000
Total Mortgages Loan | 50% - 70% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	728,000,000	487,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	728,000,000	487,000,000
Total Mortgages Loan | 50% - 70% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	1,293,000,000	882,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	1,293,000,000	882,000,000
Total Mortgages Loan | 50% - 70% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	787,000,000	1,433,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	787,000,000	1,433,000,000
Total Mortgages Loan | 50% - 70% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	366,000,000	295,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	366,000,000	295,000,000
Total Mortgages Loan | 50% - 70% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	49,000,000	45,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	49,000,000	45,000,000
Total Mortgages Loan | 70% - 90%
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	801,000,000	783,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	801,000,000	783,000,000
Total Mortgages Loan | 70% - 90% | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	169,000,000	282,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	169,000,000	282,000,000
Total Mortgages Loan | 70% - 90% | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	110,000,000	65,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	110,000,000	65,000,000
Total Mortgages Loan | 70% - 90% | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	196,000,000	231,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	196,000,000	231,000,000
Total Mortgages Loan | 70% - 90% | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	276,000,000	131,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	276,000,000	131,000,000
Total Mortgages Loan | 70% - 90% | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	50,000,000	28,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	50,000,000	28,000,000
Total Mortgages Loan | 70% - 90% | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	46,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	46,000,000
Total Mortgages Loan | 90% plus
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	27,000,000	43,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	27,000,000	43,000,000
Total Mortgages Loan | 90% plus | Greater than 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Total Mortgages Loan | 90% plus | 1.8x to 2.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Total Mortgages Loan | 90% plus | 1.5x to 1.8x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	27,000,000	28,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	27,000,000	28,000,000
Total Mortgages Loan | 90% plus | 1.2x to 1.5x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	15,000,000
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	15,000,000
Total Mortgages Loan | 90% plus | 1.0x to 1.2x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	0	0
Total Mortgages Loan | 90% plus | Less than 1.0x
Mortgage Loans on Real Estate [Line Items]
Face amount of mortgage loans	0	0
Financing Receivable, Recorded Investment, Aging [Abstract]
Total Financing Receivables	$ 0	$ 0