Fair Value of Assets and Liabilities (Details 3) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets
Balance at beginning of period	$ 2,186	$ 973	$ 1,469	$ 2,186
Total gains (losses) included in: net income		3	5	44
Total gains (losses) included in: OCI		23	(28)	(8)
Transfers into Level 3		76	59	147
Transfers out of Level 3		(559)	(433)	(294)
Sold in LBL disposition				(347)
Purchases		410	276	327
Sales		(79)	(223)	(400)
Issues		0	0
Settlements		(112)	(152)	(186)
Balance at end of period		735	973	1,469
Liabilities
Balance at beginning of period	(553)	(299)	(323)	(553)
Total gains (losses) included in: net income		5	19	9
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	0
Transfers out of Level 3		0	0	0
Purchases		0	0
Sold in LBL disposition				230
Purchases/Issues				(18)
Sales		0	0	0
Issues		(3)	(2)
Settlements		7	7	9
Balance at end of period		(290)	(299)	(323)
Fair value assets and liabilities measured on recurring basis, gain (loss) included in earnings
Gain (loss) included in earnings		8	24	53
Other investments: Free-standing derivatives		1	1	2
Free-standing derivatives, liabilities		3	8	9
Assets transferred between Level 1 and Level 2		0	0	0
Liabilities transferred between Level 1 and Level 2		0	0	0
Realized capital gains and losses
Assets
Total gains (losses) included in: net income		(9)	(8)	34
Net investment income
Assets
Total gains (losses) included in: net income		12	13	13
Interest credited to contractholder funds
Assets
Total gains (losses) included in: net income		(4)	26	(5)
Life and annuity contract benefits
Assets
Total gains (losses) included in: net income		9	(7)	15
Loss on disposition of operations
Assets
Total gains (losses) included in: net income				(4)
Fixed income securities
Assets
Balance at beginning of period	1,697	846	1,387	1,697
Total gains (losses) included in: net income		29	7	22
Total gains (losses) included in: OCI		11	(23)	6
Transfers into Level 3		76	59	143
Transfers out of Level 3		(547)	(433)	(290)
Sold in LBL disposition				4
Purchases		330	172	197
Sales		(75)	(172)	(216)
Issues		0	0
Settlements		(112)	(151)	(176)
Balance at end of period		558	846	1,387
U.S. government and agencies
Assets
Balance at beginning of period	7	5	6	7
Total gains (losses) included in: net income		0	0	0
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	0
Transfers out of Level 3		(4)	0	0
Sold in LBL disposition				0
Purchases		0	0	0
Sales		0	0	0
Issues		0	0
Settlements		(1)	(1)	(1)
Balance at end of period		0	5	6
Municipal
Assets
Balance at beginning of period	343	161	270	343
Total gains (losses) included in: net income		12	(4)	(2)
Total gains (losses) included in: OCI		(10)	(7)	18
Transfers into Level 3		6	3	0
Transfers out of Level 3		(23)	(2)	(17)
Sold in LBL disposition				0
Purchases		22	0	6
Sales		(40)	(91)	(74)
Issues		0	0
Settlements		(3)	(8)	(4)
Balance at end of period		125	161	270
Corporate - public
Assets
Balance at beginning of period		46	214
Total gains (losses) included in: net income		0	0
Total gains (losses) included in: OCI		0	0
Transfers into Level 3		41	0
Transfers out of Level 3		(43)	(175)
Purchases		47	11
Sales		(11)	0
Issues		0	0
Settlements		(2)	(4)
Balance at end of period		78	46	214
Corporate - privately placed
Assets
Balance at beginning of period		502	677
Total gains (losses) included in: net income		15	13
Total gains (losses) included in: OCI		18	(20)
Transfers into Level 3		16	13
Transfers out of Level 3		(398)	(106)
Purchases		181	79
Sales		(15)	(74)
Issues		0	0
Settlements		(56)	(80)
Balance at end of period		263	502	677
ABS - CDO
Assets
Balance at beginning of period		61	104
Total gains (losses) included in: net income		1	(1)
Total gains (losses) included in: OCI		6	4
Transfers into Level 3		10	43
Transfers out of Level 3		(43)	(52)
Purchases		40	0
Sales		(3)	(2)
Issues		0	0
Settlements		(45)	(35)
Balance at end of period		27	61	104
ABS - consumer and other
Assets
Balance at beginning of period		50	92
Total gains (losses) included in: net income		0	(1)
Total gains (losses) included in: OCI		(3)	0
Transfers into Level 3		3	0
Transfers out of Level 3		(35)	(98)
Purchases		35	70
Sales		(5)	(5)
Issues		0	0
Settlements		(3)	(8)
Balance at end of period		42	50	92
Corporate
Assets
Balance at beginning of period	1,109		891	1,109
Total gains (losses) included in: net income				24
Total gains (losses) included in: OCI				(14)
Transfers into Level 3				89
Transfers out of Level 3				(125)
Sold in LBL disposition				0
Purchases				64
Sales				(140)
Settlements				(116)
Balance at end of period				891
ABS
Assets
Balance at beginning of period	192		196	192
Total gains (losses) included in: net income				1
Total gains (losses) included in: OCI				2
Transfers into Level 3				49
Transfers out of Level 3				(144)
Sold in LBL disposition				0
Purchases				119
Sales				0
Settlements				(23)
Balance at end of period				196
ABS | LBL
Fair value assets and liabilities measured on recurring basis, gain (loss) included in earnings
Transfer from held for sale	(4)
RMBS
Assets
Balance at beginning of period	2	1	1	2
Total gains (losses) included in: net income		1	0	0
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	0
Transfers out of Level 3		0	0	0
Sold in LBL disposition				0
Purchases		0	0	0
Sales		(1)	0	0
Issues		0	0
Settlements		0	0	(1)
Balance at end of period		1	1	1
CMBS
Assets
Balance at beginning of period	43	20	23	43
Total gains (losses) included in: net income		0	0	(1)
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	5
Transfers out of Level 3		(1)	0	(4)
Sold in LBL disposition				4
Purchases		5	12	8
Sales		0	0	(1)
Issues		0	0
Settlements		(2)	(15)	(31)
Balance at end of period		22	20	23
CMBS | LBL
Fair value assets and liabilities measured on recurring basis, gain (loss) included in earnings
Transfer from held for sale	4
Redeemable preferred stock
Assets
Balance at beginning of period	1		0	1
Total gains (losses) included in: net income				0
Total gains (losses) included in: OCI				0
Transfers into Level 3				0
Transfers out of Level 3				0
Sold in LBL disposition				0
Purchases				0
Sales				(1)
Settlements				0
Balance at end of period				0
Equity securities
Assets
Balance at beginning of period	132	133	83	132
Total gains (losses) included in: net income		(32)	(3)	22
Total gains (losses) included in: OCI		12	(5)	(16)
Transfers into Level 3		0	0	0
Transfers out of Level 3		(12)	0	(2)
Sold in LBL disposition				0
Purchases		65	69	83
Sales		(4)	(11)	(136)
Issues		0	0
Settlements		1	0	0
Balance at end of period		163	133	83
Short-term investments
Assets
Balance at beginning of period	0	0	5	0
Total gains (losses) included in: net income		0	0	0
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	0
Transfers out of Level 3		0	0	0
Sold in LBL disposition				0
Purchases		15	35	45
Sales		0	(40)	(40)
Issues		0	0
Settlements		0	0	0
Balance at end of period		15	0	5
Free-standing derivatives, net
Assets
Balance at beginning of period	(5)	(7)	(7)	(5)
Total gains (losses) included in: net income		6	1	0
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	0
Transfers out of Level 3		0	0	0
Sold in LBL disposition				0
Purchases		0	0	2
Sales		0	0	0
Issues		0	0
Settlements		(1)	(1)	(4)
Balance at end of period		(2)	(7)	(7)
Other assets
Assets
Balance at beginning of period	0	1	1	0
Total gains (losses) included in: net income		0	0	1
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	0
Transfers out of Level 3		0	0	0
Sold in LBL disposition				0
Purchases		0	0	0
Sales		0	0	0
Issues		0	0
Settlements		0	0	0
Balance at end of period		1	1	1
Assets held for sale
Assets
Balance at beginning of period	362		0	362
Total gains (losses) included in: net income				(1)
Total gains (losses) included in: OCI				2
Transfers into Level 3				4
Transfers out of Level 3				(2)
Sold in LBL disposition				(351)
Purchases				0
Sales				(8)
Settlements				(6)
Balance at end of period				0
Contractholder funds: Derivatives embedded in life and annuity contracts
Liabilities
Balance at beginning of period	(307)	(299)	(323)	(307)
Total gains (losses) included in: net income		5	19	(8)
Total gains (losses) included in: OCI		0	0	0
Transfers into Level 3		0	0	0
Transfers out of Level 3		0	0	0
Purchases		0	0
Sold in LBL disposition				0
Purchases/Issues				(14)
Sales		0	0	0
Issues		(3)	(2)
Settlements		7	7	6
Balance at end of period		(290)	(299)	(323)
Liabilities held for sale
Liabilities
Balance at beginning of period	$ (246)		0	(246)
Total gains (losses) included in: net income		$ 0	$ 0	17
Total gains (losses) included in: OCI				0
Transfers into Level 3				0
Transfers out of Level 3				0
Sold in LBL disposition				230
Purchases/Issues				(4)
Sales				0
Settlements				3
Balance at end of period				$ 0