Acquisitions - Acquisition of Atria Wealth Solutions, Inc. (Details) - USD ($) $ in Thousands		3 Months Ended
Oct. 01, 2024	Dec. 31, 2025
Fair value of consideration transferred
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		$ 194,000
Business Acquisition, Transaction Costs	$ 18,000
Atria Wealth Solutions, Inc. Acquisition
Fair value of consideration transferred
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 330,000
Other intangibles	$ 620,100
Weighted-Average Life Remaining (in years)	16 years
Business Combination, Acquisition Related Costs		$ 18,000
Atria Wealth Solutions, Inc. Acquisition \| Institutional Relationships
Fair value of consideration transferred
Other intangibles	$ 195,400
Atria Wealth Solutions, Inc. Acquisition \| Advisor Relationships
Fair value of consideration transferred
Other intangibles	$ 424,700

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 985
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-Section 50
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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
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-Section 50
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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Topic 805
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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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