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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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Investments - Allowance for Credit Losses on Mortgage Loans (Details) - USD ($)		3 Months Ended	9 Months Ended
	Jan. 01, 2020	Sep. 30, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff		$ 0	$ (1,000,000)
Mortgage loans allowance for credit losses		313,000,000	313,000,000		$ 11,000,000
Commercial mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff		0	0
Mortgage loans allowance for credit losses		232,000,000	232,000,000	$ 294,000,000	10,000,000
Financing Receivable, Credit Loss, Expense (Reversal)		(62,000,000)	55,000,000
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		0	0
Residential mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff		0	(1,000,000)
Mortgage loans allowance for credit losses		96,000,000	96,000,000	85,000,000	1,000,000
Financing Receivable, Credit Loss, Expense (Reversal)		8,000,000	50,000,000
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		3,000,000	3,000,000
Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff		0	0
Mortgage loans allowance for credit losses		13,000,000	13,000,000	20,000,000	0
Financing Receivable, Credit Loss, Expense (Reversal)		(7,000,000)	2,000,000
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		0	0
Related Party
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses					0	$ 15,000,000
Accounting Standards Update 2016-13 [Member] \| Commercial mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	$ 167,000,000	0
Accounting Standards Update 2016-13 [Member] \| Residential mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	43,000,000	0
Accounting Standards Update 2016-13 [Member] \| Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	11,000,000	0
Investments including related party
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		341,000,000	341,000,000	$ 399,000,000	$ 11,000,000
Financing Receivable, Credit Loss, Expense (Reversal)		(61,000,000)	107,000,000
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		3,000,000	$ 3,000,000
Investments including related party \| Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	$ 221,000,000	$ 0