- Fair Value Level 3 Rollforward Recurring Basis (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
FG VIEs' assets, at fair value [Member]
Fair Value Level 3 Rollforward
Fair value at beginning of period	$ 569	$ 700
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	68	2
Other comprehensive income (loss)	0	0
Purchases	0	0
Sales	(51)
Settlements	(139)	0
VIE consolidations	6	(116)
VIE deconsolidations	(11)	(17)
Transfers into Level 3	0
Fair value at end of period	442	569
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI	77	13
Assets of consolidated investment vehicles [Member]
Fair Value Level 3 Rollforward
Fair value at beginning of period	0
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	0
Other comprehensive income (loss)	0
Purchases	64
Sales	0
Settlements	0
VIE consolidations	0
VIE deconsolidations	0
Transfers into Level 3	0
Fair value at end of period	64	0
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI	0
Other [Member]
Fair Value Level 3 Rollforward
Fair value at beginning of period	77	64
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	(22)	14
Other comprehensive income (loss)	0	0
Purchases	0	0
Sales	0
Settlements	0	0
VIE consolidations	0	(1)
VIE deconsolidations	0	0
Transfers into Level 3	0
Fair value at end of period	55	77
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI	(22)	14
Obligations of state and political subdivisions [Member] \| Fixed Maturities [Member]
Fair Value Level 3 Rollforward
Fair value at beginning of period	99	76
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	6	3
Other comprehensive income (loss)	(1)	18
Purchases	6	4
Sales	0
Settlements	(3)	0
VIE consolidations	0	(2)
VIE deconsolidations	0	0
Transfers into Level 3	0
Fair value at end of period	107	99
Corporate securities [Member] \| Fixed Maturities [Member]
Fair Value Level 3 Rollforward
Fair value at beginning of period	56	67
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	(8)	(14)
Other comprehensive income (loss)	(7)	3
Purchases	0	0
Sales	0
Settlements	0	0
VIE consolidations	0	0
VIE deconsolidations	0	0
Transfers into Level 3	0
Fair value at end of period	41	56
Residential Mortgage-Backed Securities (RMBS) [Member] \| Fixed Maturities [Member]
Fair Value Level 3 Rollforward
Fair value at beginning of period	309	334
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	17	21
Other comprehensive income (loss)	25	(17)
Purchases	11	35
Sales	0
Settlements	(54)	0
VIE consolidations	0	(64)
VIE deconsolidations	0	0
Transfers into Level 3	0
Fair value at end of period	308	309
Asset-backed Securities [Member] \| Fixed Maturities [Member]
Fair Value Level 3 Rollforward
Fair value at beginning of period	947	787
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	58	57
Other comprehensive income (loss)	(91)	(40)
Purchases	20	189
Sales	(29)
Settlements	(248)	0
VIE consolidations	0	(46)
VIE deconsolidations	0	0
Transfers into Level 3	1
Fair value at end of period	658	947
Other Comprehensive Income (Loss) [Member] \| Other [Member]
Total pretax realized and unrealized gains/(losses) recorded in:
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI		0
Other Comprehensive Income (Loss) [Member] \| Obligations of state and political subdivisions [Member] \| Fixed Maturities [Member]
Total pretax realized and unrealized gains/(losses) recorded in:
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI	0	18
Other Comprehensive Income (Loss) [Member] \| Corporate securities [Member] \| Fixed Maturities [Member]
Total pretax realized and unrealized gains/(losses) recorded in:
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI	(7)	3
Other Comprehensive Income (Loss) [Member] \| Residential Mortgage-Backed Securities (RMBS) [Member] \| Fixed Maturities [Member]
Total pretax realized and unrealized gains/(losses) recorded in:
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI	25	(14)
Other Comprehensive Income (Loss) [Member] \| Asset-backed Securities [Member] \| Fixed Maturities [Member]
Total pretax realized and unrealized gains/(losses) recorded in:
Change in unrealized gains/(losses) related to financial instruments held, Included in OCI	15	(38)
FG VIEs' liabilities with recourse, at fair value [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of period	(517)	(627)
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	(32)	(1)
Other comprehensive income (loss)	5	2
Issuances	0
Purchases		0
Settlements	173	0
VIE consolidations	(5)	108
VIE deconsolidations	9	1
Fair value at end of period	(367)	(517)
Change in unrealized gains/(losses) related to financial instruments held	(31)	1
FG VIEs' liabilities with recourse, at fair value [Member] \| Other Comprehensive Income (Loss) [Member]
Total pretax realized and unrealized gains/(losses) recorded in:
Change in unrealized gains/(losses) related to financial instruments held	5	2
VIEs' liabilities without recourse, at fair value [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of period	(102)	(130)
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	(9)	4
Other comprehensive income (loss)	0	0
Issuances	0
Purchases		0
Settlements	8	0
VIE consolidations	(1)	8
VIE deconsolidations	2	16
Fair value at end of period	(102)	(102)
Change in unrealized gains/(losses) related to financial instruments held	(17)	3
Liabilities of consolidated investment vehicles [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of period	0
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	(9)
Other comprehensive income (loss)	0
Issuances	(472)
Settlements	0
VIE consolidations	0
VIE deconsolidations	0
Fair value at end of period	(481)	0
Change in unrealized gains/(losses) related to financial instruments held	(9)
Credit Risk Contract [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair value at beginning of period	(207)	(269)
Total pretax realized and unrealized gains/(losses) recorded in:
Net income (loss)	(6)	112
Other comprehensive income (loss)	0	0
Purchases		0
Issuances	0
Settlements	28	(68)
VIE consolidations	0	18
VIE deconsolidations	0	0
Fair value at end of period	(185)	(207)
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss)	$ 3	$ 122

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