Investments (Credit Quality of Commercial Mortgage Loans) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage Loans, Gross	$ 93,227	$ 84,290
Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	3,068
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	8,829
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	7,441
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,714
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	8,615
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	24,961
Financing Receivable, Revolving	2,698
Mortgage Loans, Gross	$ 60,326	$ 52,502
Loans Receivable Commercial Mortgage Percentage	100.00%
Commercial Mortgage Loans | Greater than 1.20x
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 2,088
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	7,387
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	6,880
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,372
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	7,243
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	21,644
Financing Receivable, Revolving	2,698
Mortgage Loans, Gross	$ 52,312
Loans Receivable Commercial Mortgage Percentage	86.70%
Commercial Mortgage Loans | 1.00x - 1.20x
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 666
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	590
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	543
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	849
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,986
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 4,634
Loans Receivable Commercial Mortgage Percentage	7.70%
Commercial Mortgage Loans | Less than 1.00x
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 314
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	852
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	18
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	342
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	523
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,331
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 3,380
Loans Receivable Commercial Mortgage Percentage	5.60%
Commercial Mortgage Loans | Less than 65%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 2,592
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,724
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	3,392
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,787
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4,220
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	13,082
Financing Receivable, Revolving	2,698
Mortgage Loans, Gross	$ 30,495
Loans Receivable Commercial Mortgage Percentage	50.60%
Commercial Mortgage Loans | 65% to 75%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 372
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,465
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	2,737
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,651
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,636
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	6,114
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 16,975
Loans Receivable Commercial Mortgage Percentage	28.10%
Commercial Mortgage Loans | 76% to 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 58
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	846
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	335
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	377
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,367
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,692
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 4,675
Loans Receivable Commercial Mortgage Percentage	7.70%
Commercial Mortgage Loans | Greater than 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 46
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	794
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	977
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	899
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,392
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	4,073
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 8,181
Loans Receivable Commercial Mortgage Percentage	13.60%