Collateral cash and securities received in exchange of value of securities lent in order to reduce credit risk.

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Separate account collateral held under securities lending agreements.

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Fair Value of Separate Account Collateral obtained under securities lending agreements.

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- Definition

Significant accounting policies.

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No definition available.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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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.

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- Definition

Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used.

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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.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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- Definition

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
	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%