Segment Reporting (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) level3FinancialInstruments	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting, Revenue Reconciling Item [Line Items]
Number of Reportable Segments | level3FinancialInstruments			3
Revenues	$ 86	$ 49	$ 206	$ 178
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	6	(18)	9	1
Provision (benefit) for income taxes	1	11	1	13
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	5	(28)	8	(11)
Premiums Earned, Net	14	11	28	25
Net Investment Income	(21)	42	(16)	91
Amortization of intangible assets	13	14	28	33
Interest Expense	45	50	89	100
Total assets	10,061	12,907	10,061	12,907	$ 12,303
Premiums Written, Net	9	(13)	21	(21)
Derivative, Gain (Loss) on Derivative, Net	29	(11)	86	14
Net realized gains (losses) on extinguishment of debt	57	0	57	33
Insurance Commissions and Fees	6	6	15	13
Other revenues, operating	2	1	36	2
Losses and loss expenses (benefit)	(12)	(26)	12	(18)
Operating Expenses	29	24	58	54
Insurance Commissions	4	4	8	7
Depreciation	0	0	1	1
Benefits, Losses and Expenses	80	66	197	177
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest		0	0	0
Net income attributable to common shareholders	5	(29)	7	(12)
Financial Guarantee
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	75	42	184	160
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	7	(16)	13	8
Premiums Earned, Net	11	11	24	25
Net Investment Income	(22)	41	(18)	90
Amortization of intangible assets	13	13	26	31
Interest Expense	45	50	89	100
Total assets	9,579	12,532	9,579	12,532
Derivative, Gain (Loss) on Derivative, Net	28	(11)	85	14
Net realized gains (losses) on extinguishment of debt	57	0	57	33
Insurance Commissions and Fees
Other revenues, operating	1	1	35	(2)
Losses and loss expenses (benefit)	(14)	(26)	9	(18)
Operating Expenses	23	21	44	38
Depreciation	0	0	1	1
Benefits, Losses and Expenses	68	59	170	152
Specialty Property & Casualty Program
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	4	0	5	0
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	(1)	(2)	(4)	(3)
Premiums Earned, Net	3	0	4	0
Net Investment Income	0	0	1	0
Interest Expense
Total assets	229	109	229	109
Net realized gains (losses) on extinguishment of debt		0		0
Insurance Commissions and Fees
Other revenues, operating	0	0	1	0
Losses and loss expenses (benefit)	2	0	3	0
Operating Expenses	3	2	7	3
Depreciation	0	0	0	0
Benefits, Losses and Expenses	5	2	9	3
Managing General Agency Underwriter
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	6	6	15	13
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	0	0	2	2
Amortization of intangible assets	1	1	1	1
Interest Expense
Total assets	94	97	94	97
Derivative, Gain (Loss) on Derivative, Net
Net realized gains (losses) on extinguishment of debt
Insurance Commissions and Fees	6	6	15	13
Other revenues, operating	0	0	0	0
Operating Expenses	2	1	3	3
Insurance Commissions	4	4	8	7
Depreciation	0	0	0	0
Benefits, Losses and Expenses	6	6	13	11
Corporate and Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	2	0	2	4
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	1	0	(3)	(6)
Net Investment Income	1	0	1	0
Interest Expense
Total assets	159	169	159	169
Derivative, Gain (Loss) on Derivative, Net	1		1
Net realized gains (losses) on extinguishment of debt
Insurance Commissions and Fees
Other revenues, operating	0	0	0	4
Operating Expenses	1	0	4	10
Depreciation	0	0	0	0
Benefits, Losses and Expenses	1	0	4	10
Surplus Notes	$ 61	$ 116	$ 61	$ 116