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v3.25.2

Long-duration insurance contracts - Summary of changes in discounted present values of expected future policy benefits and expected future net premiums (Detail) - USD ($) $ in Millions | 6 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward] |  |
Balance at June 30 | $ 17,865 | $ 17,500
Periodic Payment Annuity [Member] |  |
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward] |  |
Balance at beginning of year | 10,276 | 11,212
Balance at beginning of year at original discount rate | 11,757 | 11,681
Effect of actual versus expected experience | (20) | 4
Change in benefits, net | (240) | (235)
Interest accrual | 277 | 273
Foreign currency effect | 136 | 15
Ending balance at original discount rate | 11,910 | 11,738
Effect of changes in discount rate assumptions | (1,453) | (1,360)
Expected future policy benefits at June 30 | 10,457 | 10,378
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward] |  |
Balance at June 30 | 10,457 | 10,378
Liabilities for future policy benefits at June 30, net of reinsurance recoverables | 10,457 | 10,378
Life and Health [Member] |  |
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward] |  |
Balance at beginning of year | 43,784 | 52,665
Balance at beginning of year at original discount rate | 55,170 | 65,871
Effect of cash flow assumption changes | (98) | (324)
Effect of actual versus expected experience | 246 | (12,836)
Change in benefits, net | (887) | (943)
Interest accrual | 646 | 575
Foreign currency effect | 1,489 | (459)
Ending balance at original discount rate | 56,566 | 51,884
Effect of changes in discount rate assumptions | (12,232) | (12,739)
Expected future policy benefits at June 30 | 44,334 | 39,145
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward] |  |
Balance at beginning of year | 39,294 | 46,916
Balance at beginning of year at original discount rate | 49,500 | 58,731
Effect of cash flow assumption changes | (66) | (326)
Effect of actual versus expected experience | 204 | (11,225)
Change in premiums, net | (884) | (876)
Interest accrual | 579 | 507
Foreign currency effect | 1,395 | (436)
Ending balance at original discount rate | 50,728 | 46,375
Effect of changes in discount rate assumptions | (10,898) | (11,397)
Expected future net premiums at June 30 | 39,830 | 34,978
Balance at June 30 | 4,504 | 4,167
Reinsurance recoverables | (51) | (49)
Liabilities for future policy benefits at June 30, net of reinsurance recoverables | $ 4,453 | $ 4,118

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- Definition Amount, before tax, of accumulated other comprehensive income (loss) (AOCI) from (increase) decrease in expected future policy benefit component of liability for future policy benefit from change in discount rate. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-6 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 13I -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-13I Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29E -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-29E Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (g)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480016/944-40-65-2 + Details
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- Definition Amount of interest expense for expected future policy benefit and expense component of liability for future policy benefit. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-6 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29E -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-29E Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (g)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480016/944-40-65-2 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 13I -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-13I + Details
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