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 Investments - Allowance for Credit Losses on Mortgage Loans (Details) - USD ($)		3 Months Ended	6 Months Ended
	Jan. 01, 2020	Jun. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff		$ (1,000,000)	$ (1,000,000)
Mortgage loans allowance for credit losses		352,000,000	352,000,000		$ 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		294,000,000	294,000,000	$ 343,000,000	10,000,000
Financing Receivable, Credit Loss, Expense (Reversal)		(49,000,000)	117,000,000
Residential mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff		(1,000,000)	(1,000,000)
Mortgage loans allowance for credit losses		85,000,000	85,000,000	81,000,000	1,000,000
Financing Receivable, Credit Loss, Expense (Reversal)		5,000,000	42,000,000
Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Writeoff		0	0
Mortgage loans allowance for credit losses		20,000,000	20,000,000	12,000,000	0
Financing Receivable, Credit Loss, Expense (Reversal)		8,000,000	9,000,000
Related Party
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		27,000,000	27,000,000		0
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		399,000,000	399,000,000	$ 436,000,000	$ 11,000,000
Financing Receivable, Credit Loss, Expense (Reversal)		(36,000,000)	$ 168,000,000
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