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v3.25.3

Income Taxes and Related Payments - Changes in Deferred Tax Assets (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Deferred Tax Asset - Amortizable Basis |  |
Deferred tax assets, beginning | $ 354,773 |
2025 Holdings Common Unit Exchanges | 619 |
Amortization | (35,747) |
Change in estimate | 2 |
Deferred tax assets, ending | 319,647 |
Amounts Payable Under TRAs |  |
Amounts payable under tax receivable, beginning agreements | 341,461 |
Establishment of amounts payable under tax receivable agreements | 526 | $ 14,011
Payments under the tax receivable agreements | (38,286) | $ (36,659)
Amounts payable under tax receivable, ending agreements | 303,145 |
Capital Unit |  |
Amounts Payable Under TRAs |  |
Establishment of amounts payable under tax receivable agreements | $ 527 |

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- Definition Amounts payable under tax receivable agreement. + References No definition available. + Details
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- Definition Deferred Tax Assets, Exchanges + References No definition available. + Details
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- Definition Deferred tax assets recorded as a result of the step-up of tax basis from the H&F Corp Merger and the purchase of Class A common units by APAM. + References No definition available. + Details
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- Definition Initial establishment of the estimated liability associated with the tax benefits expected to be realized as a result of the tax receivable agreements. + References No definition available. + Details
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- Definition Tax Receivable Agreement Payments + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition Tax Receivable Agreements [Roll Forward] + References No definition available. + Details
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Balance Type: | na
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- Definition Amount of other income tax expense (benefit). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-9 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(1)(Note 1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-10 + Details
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- Details
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