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

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Investments Investments - Allowance for Credit Losses on Mortgage Loans (Details) - USD ($) $ in Millions		3 Months Ended
	Jan. 01, 2020	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		$ 394	$ 11
Commercial mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		343	10
Financing Receivable, Credit Loss, Expense (Reversal)		166
Residential mortgage loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		81	1
Financing Receivable, Credit Loss, Expense (Reversal)		37
Related Party
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		30	0
Related Party \| Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		12	0
Financing Receivable, Credit Loss, Expense (Reversal)		1
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
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
Accounting Standards Update 2016-13 [Member] \| Related Party \| Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	11
Investments including related party
Financing Receivable, Allowance for Credit Loss [Line Items]
Mortgage loans allowance for credit losses		436	$ 11
Financing Receivable, Credit Loss, Expense (Reversal)		$ 204
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