Investments - Schedule of AFS Securities (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	$ 45	$ 1,728
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party
Debt Securities, Available-for-sale [Line Items]
Amortized Costs		58,777
Gross Unrealized Gains		2,759
Gross Unrealized Losses		(247)
Available-for-sale Securities		61,289
Amortized Cost	59,744	58,506
Gross Unrealized Gains	1,236	2,752
Gross Unrealized Losses	(1,098)	(246)
Fair Value	59,882	61,012
Equity securities
Cost		271
Gross Unrealized Gains		7
Gross Unrealized Losses		(1)
Fair Value		277
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | U.S. government and agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	143	63
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(1)	(2)
Fair Value	142	62
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | U.S. state, municipal and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,142	996
Gross Unrealized Gains	103	171
Gross Unrealized Losses	(8)	(2)
Fair Value	1,237	1,165
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | Foreign governments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	180	2,575
Gross Unrealized Gains	3	116
Gross Unrealized Losses	(3)	(8)
Fair Value	180	2,683
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | Corporate
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	37,819	35,173
Gross Unrealized Gains	447	1,658
Gross Unrealized Losses	(947)	(171)
Fair Value	37,319	36,660
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | CLO
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,325	5,039
Gross Unrealized Gains	15	53
Gross Unrealized Losses	(38)	(8)
Fair Value	5,302	5,084
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | ABS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,869	3,945
Gross Unrealized Gains	29	53
Gross Unrealized Losses	(43)	(27)
Fair Value	4,855	3,971
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | CMBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,343	1,994
Gross Unrealized Gains	29	48
Gross Unrealized Losses	(48)	(21)
Fair Value	2,324	2,021
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | RMBS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,923	8,721
Gross Unrealized Gains	610	652
Gross Unrealized Losses	(10)	(7)
Fair Value	8,523	9,366
Consolidated Entity Excluding Variable Interest Entities (VIE)
Debt Securities, Available-for-sale [Line Items]
Amortized Costs		59,176
Gross Unrealized Gains		2,766
Gross Unrealized Losses		(247)
Available-for-sale Securities		61,695
Amortized Cost	60,994
Gross Unrealized Gains	1,238
Gross Unrealized Losses	(1,107)
Fair Value	61,125
Consolidated Entity Excluding Variable Interest Entities (VIE) | Related Party
Debt Securities, Available-for-sale [Line Items]
Amortized Costs		399
Gross Unrealized Gains		7
Gross Unrealized Losses		0
Available-for-sale Securities		406
Amortized Cost	1,250	399
Gross Unrealized Gains	2
Gross Unrealized Losses	(9)
Fair Value	1,243	406
Consolidated Entity Excluding Variable Interest Entities (VIE) | Related Party | CLO
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	612	353
Gross Unrealized Gains	1	7
Gross Unrealized Losses	(4)	0
Fair Value	609	360
Consolidated Entity Excluding Variable Interest Entities (VIE) | Related Party | ABS
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	638	46
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(5)	0
Fair Value	634	46
OTTI
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	(17)	(13)
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	17	13
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | U.S. government and agencies
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	0	0
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | U.S. state, municipal and political subdivisions
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	0	0
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | Foreign governments
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	0	0
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | Corporate
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	1	0
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | CLO
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	0	0
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | ABS
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	0	1
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | CMBS
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	7	1
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party | RMBS
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	9	11
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE)
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	17	13
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) | Related Party
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	0	0
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) | Related Party | CLO
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	0	0
OTTI | Consolidated Entity Excluding Variable Interest Entities (VIE) | Related Party | ABS
Debt Securities, Available-for-sale [Line Items]
OTTI in AOCI	$ 0	$ 0