Investments (Fair Value and Losses by Investment Category and Length of Time in a Loss Position) (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 35,778	$ 18,962
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	888	659
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	31,890	32,102
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	7,254	6,290
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	67,668	51,064
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	8,142	6,949
Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	34,528	18,291
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	836	633
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	31,540	31,831
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	7,195	6,256
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	66,068	50,122
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	8,031	6,889
Non-investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,250	671
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	52	26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	350	271
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	59	34
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,600	942
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	111	60
Corporate Debt Securities [Member] \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	23,623	10,591
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	453	255
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	21,809	22,666
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	3,953	3,635
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	45,432	33,257
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	4,406	3,890
Corporate Debt Securities [Member] \| Non-investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,009	652
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	32	25
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	331	258
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	58	31
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,340	910
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	90	56
Canadian and Canadian provincial governments \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	548	1,096
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	9	34
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	584	426
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	76	72
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,132	1,522
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	85	106
Residential mortgage-backed securities \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	707	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	5	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	525	562
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	73	72
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,232	562
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	78	72
Asset-backed Securities [Member] \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	2,702	2,324
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	23	15
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,164	1,149
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	136	141
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	3,866	3,473
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	159	156
Asset-backed Securities [Member] \| Non-investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	241	19
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	20	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	19	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	1	0
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	260	19
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	21	1
Commercial mortgage-backed securities \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	870	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	9	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	643	705
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	48	50
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,513	705
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	57	50
US Government Agencies Debt Securities [Member] \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	779	406
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	4	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	482	542
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	253	247
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	1,261	948
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	257	248
US States and Political Subdivisions Debt Securities [Member] \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	170	73
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	5	1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	391	451
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	79	78
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	561	524
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	84	79
Debt Security, Government, Non-US [Member] \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,739	1,382
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	43	26
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,671	1,901
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	367	350
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	3,410	3,283
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	410	376
Debt Security, Government, Non-US [Member] \| Non-investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0	13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	3
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	0	13
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	0	3
JAPAN \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	2,700	1,274
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	126	209
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	3,976	3,351
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	2,112	1,607
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	6,676	4,625
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	2,238	1,816
Korean Government Debt Securities \| Investment grade securities
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	690	1,145
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	159	92
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	295	78
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	98	4
Debt Securities, Available-for-sale, Unrealized Loss Position, Total	985	1,223
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 257	$ 96

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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