Investments (Mortgage Loans Allowance for Credit Loss Rollforward by Portfolio Segment) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	$ 634	$ 590
Provision (release)	(6)	(8)
Initial credit losses on PCD loans (1)	0	2
Charge-offs, net of recoveries	(142)	(14)
Balance, end of period	486	570
Commercial Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	340	252
Provision (release)	(16)	22
Initial credit losses on PCD loans (1)	0	0
Charge-offs, net of recoveries	(119)	0
Balance, end of period	205	274
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	206	232
Provision (release)	(31)	(23)
Initial credit losses on PCD loans (1)	0	2
Charge-offs, net of recoveries	(1)	(1)
Balance, end of period	174	210
Agricultural Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	88	106
Provision (release)	41	(7)
Initial credit losses on PCD loans (1)	0	0
Charge-offs, net of recoveries	(22)	(13)
Balance, end of period	$ 107	$ 86