Lending Activities - Rollforward of the changes in the allowance for credit losses on Mortgage and other loans receivable (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Changes in the allowance for losses on Mortgage and other loans receivable
Allowance, beginning of period	$ 617	$ 787	$ 629	$ 814
Loans charged off	0	0	(4)	0
Net charge-offs	0	0	(4)	0
Addition to (release of) allowance for loan losses	(14)	(86)	(22)	(113)
Allowance, end of period	603	701	603	701
Off-balance-sheet commitments	89		89		$ 71
Loans modified in a troubled debt restructuring	115	46	115	46
Commercial mortgage loans
Changes in the allowance for losses on Mortgage and other loans receivable
Allowance, beginning of period	533	662	545	685
Loans charged off	0	0	(4)	0
Net charge-offs	0	0	(4)	0
Addition to (release of) allowance for loan losses	(8)	(75)	(16)	(98)
Allowance, end of period	525	587	525	587
Off-balance-sheet commitments	89	81	89	81
Other loans
Changes in the allowance for losses on Mortgage and other loans receivable
Allowance, beginning of period	84	125	84	129
Loans charged off	0	0	0	0
Net charge-offs	0	0	0	0
Addition to (release of) allowance for loan losses	(6)	(11)	(6)	(15)
Allowance, end of period	$ 78	$ 114	$ 78	$ 114

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

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

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Amount of financing receivable modified as troubled debt restructuring.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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

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