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v3.25.4

Significant Accounting Policies - Additional Information (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2025 USD ($) Segment | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Significant Accounting Policies [Line Items] |  |  |
Fair value of loaned securities held | $ 13,300 | $ 9,900 |
Fair value of collateral loan under these securities lending agreements | 14,400 | 10,600 |
Separate account collateral held under securities lending agreements | 7,922 | 6,059 |
Fair value of securities received as collateral have been resold or repledged | $ 0 | 0 |
Number of business segments | Segment | 1 |  |
Restricted Stock Units (RSUs) [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Discrete income tax benefit for vested stock awards | $ 67 | $ 37 | $ 41
Equipment and Computer Software [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful life | 3 years |  |
Minimum [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
VIE, economic interest percentage | 10.00% |  |
Collateral cash and securities received in exchange of value of securities lent in order to reduce counterparty risk | 102.00% |  |
Minimum [Member] | Investee [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Ownership percentage | 20.00% |  |
Minimum [Member] | WMC [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Ownership percentage | 49.90% |  |
Maximum [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Collateral cash and securities received in exchange of value of securities lent in order to reduce counterparty risk | 112.00% |  |
Maximum [Member] | Investee [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Ownership percentage | 50.00% |  |
Maximum [Member] | WMC [Member] |  |  |
Significant Accounting Policies [Line Items] |  |  |
Ownership percentage | 50.10% |  |

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- Definition Collateral cash and securities received in exchange of value of securities lent in order to reduce credit risk. + References No definition available. + Details
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- Definition Separate account collateral held under securities lending agreements. + References No definition available. + Details
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- Definition Fair Value of Separate Account Collateral obtained under securities lending agreements. + References No definition available. + Details
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- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481687/323-10-50-3 + Details
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- Definition Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 49 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-49 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-18 + Details
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