Income Taxes - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount		$ (11)	$ 0	$ (11)	$ 0
Effective Income Tax Rate Reconciliation, Disposition of Business, Amount		(8)	$ 0	(8)	$ 0
Proceeds from Income Tax Refunds	$ 206
Non-insurance carryback [Member]
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount		6
Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards		11		11
Deferred Tax Assets, Valuation Allowance		$ 11		$ 11
Interest Income [Member]
Operating Loss Carryforwards [Line Items]
Proceeds from Income Tax Refunds	$ 1