Investments (Credit Quality of Commercial Mortgage Loans) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage Loans, Gross	$ 86,264	$ 84,290
Commercial Mortgage Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	864
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	7,684
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	7,026
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,689
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	7,663
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	22,886
Financing Receivable, Revolving	2,885
Mortgage Loans, Gross	$ 53,697	$ 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	$ 383
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	6,831
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	6,331
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	4,330
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	6,888
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	20,627
Financing Receivable, Revolving	2,385
Mortgage Loans, Gross	$ 47,775
Loans Receivable Commercial Mortgage Percentage	89.00%
Commercial Mortgage Loans | 1.00x - 1.20x
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 481
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	566
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	345
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	69
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	300
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,201
Financing Receivable, Revolving	204
Mortgage Loans, Gross	$ 3,166
Loans Receivable Commercial Mortgage Percentage	5.90%
Commercial Mortgage Loans | Less than 1.00x
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	287
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	350
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	290
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	475
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	1,058
Financing Receivable, Revolving	296
Mortgage Loans, Gross	$ 2,756
Loans Receivable Commercial Mortgage Percentage	5.10%
Commercial Mortgage Loans | Less than 65%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 864
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	5,118
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	5,672
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	3,515
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	5,169
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	18,049
Financing Receivable, Revolving	2,885
Mortgage Loans, Gross	$ 41,272
Loans Receivable Commercial Mortgage Percentage	76.90%
Commercial Mortgage Loans | 65% to 75%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,136
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	1,295
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	1,056
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	1,605
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	3,162
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 9,254
Loans Receivable Commercial Mortgage Percentage	17.20%
Commercial Mortgage Loans | 76% to 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	348
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	59
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	100
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	311
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	709
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 1,527
Loans Receivable Commercial Mortgage Percentage	2.80%
Commercial Mortgage Loans | Greater than 80%
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Year One, Originated, Current Fiscal Year	$ 0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	82
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year	18
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year	578
Financing Receivable, Originated, More than Five Years before Current Fiscal Year	966
Financing Receivable, Revolving	0
Mortgage Loans, Gross	$ 1,644
Loans Receivable Commercial Mortgage Percentage	3.10%