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Effective Income Tax Rate Reconciliation, Taxes on Reinsurance, Amount

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Income Taxes - Effective Tax Rate Reconciliation and Pretax Income (Loss) and Revenue by Tax Jurisdiction (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pre-tax Income Taxes and Revenue [Line Items]
Expected tax provision (benefit)									$ 91	$ 97	$ 300
Tax-exempt interest									(19)	(23)	(49)
Bargain purchase gain									0	0	(20)
Change in liability for uncertain tax positions									1	(15)	(26)
Effect of provision to tax return filing adjustments									(6)	(1)	(8)
State tax									1	6	9
Taxes on reinsurance									(5)	6	(4)
Effect of adjustments to the provisional amounts as a result of 2017 Tax Cuts and Jobs Act									0	(4)	61
Foreign taxes									6	0	4
Other									(6)	(7)	(6)
Total provision (benefit) for income taxes	$ 2	$ 17	$ 40	$ 4	$ 13	$ 14	$ 12	$ 20	$ 63	$ 59	$ 261
Effective tax rate (as a percent)									13.70%	10.20%	26.30%
Income (loss) before income taxes and equity in net earnings of investees	137	86	181	56	100	176	86	217	$ 460	$ 579	$ 991
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	$ 138	$ 86	$ 182	$ 58	$ 101	$ 175	$ 87	$ 217	464	580	991
Revenues									963	1,001	1,739
United States [Member]
Pre-tax Income Taxes and Revenue [Line Items]
Income (loss) before income taxes and equity in net earnings of investees									440	461	873
Revenues									779	801	1,543
Bermuda [Member]
Pre-tax Income Taxes and Revenue [Line Items]
Income (loss) before income taxes and equity in net earnings of investees									33	121	145
Revenues									146	177	216
United Kingdom and Other [Member]
Pre-tax Income Taxes and Revenue [Line Items]
Income (loss) before income taxes and equity in net earnings of investees									(9)	(2)	(27)
Revenues									$ 38	$ 23	$ (20)