Investments (Credit Quality of Commercial Mortgage Loans) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage Loans, Gross	$ 92,935	$ 84,290
Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	2,282
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	8,738
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	7,399
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,723
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	8,649
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	25,555
Financing Receivable, Revolving	2,705
Mortgage Loans, Gross	$ 60,051	$ 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	$ 1,570
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	7,068
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	6,841
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,348
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	7,280
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	22,272
Financing Receivable, Revolving	2,408
Mortgage Loans, Gross	$ 51,787
Loans Receivable Commercial Mortgage Percentage	86.20%
Commercial Mortgage Loans | 1.00x - 1.20x
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 522
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	637
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	514
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	35
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	640
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,867
Financing Receivable, Revolving	297
Mortgage Loans, Gross	$ 4,512
Loans Receivable Commercial Mortgage Percentage	7.50%
Commercial Mortgage Loans | Less than 1.00x
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 190
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,033
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	44
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	340
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	729
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,416
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 3,752
Loans Receivable Commercial Mortgage Percentage	6.30%
Commercial Mortgage Loans | Less than 65%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 2,058
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	5,013
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	4,334
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,951
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	4,210
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	13,598
Financing Receivable, Revolving	2,705
Mortgage Loans, Gross	$ 33,869
Loans Receivable Commercial Mortgage Percentage	56.40%
Commercial Mortgage Loans | 65% to 75%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 210
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	3,154
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,986
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,696
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	2,122
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	6,379
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 15,547
Loans Receivable Commercial Mortgage Percentage	25.90%
Commercial Mortgage Loans | 76% to 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 4
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	414
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	284
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	385
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,271
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,763
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 4,121
Loans Receivable Commercial Mortgage Percentage	6.90%
Commercial Mortgage Loans | Greater than 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 10
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	157
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	795
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	691
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,046
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	3,815
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 6,514
Loans Receivable Commercial Mortgage Percentage	10.80%