Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale.

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Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows.

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Investments - Rollforward of credit loss allowance for fixed income securities (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Mar. 31, 2020	Jan. 01, 2020
Credit Losses on Fixed Income Securities
Net increases related to credit losses previously reported	$ (1)	$ 0
Reduction of allowance related to sales	1	2
Fixed income securities
Credit Losses on Fixed Income Securities
Beginning balance	(7)	0
Credit losses on securities for which credit losses not previously reported	(1)	(10)
Ending balance	(8)	(8)
Fixed income securities	8	8	$ 4	$ 0
Municipal
Credit Losses on Fixed Income Securities
Ending balance	(3)	(3)
Fixed income securities	3	3
Corporate
Credit Losses on Fixed Income Securities
Ending balance	(2)	(2)
Fixed income securities	2	2
ABS
Credit Losses on Fixed Income Securities
Ending balance	(2)	(2)
Fixed income securities	2	2
MBS
Credit Losses on Fixed Income Securities
Ending balance	(1)	(1)
Fixed income securities	$ 1	$ 1