v3.25.3

Borrowings and Debt - Schedule of Long Term Debt (Details) - USD ($)	Oct. 28, 2025	Sep. 30, 2025	Dec. 31, 2024	Aug. 29, 2024
Fair Value, Inputs, Level 2
Debt Instrument [Line Items]
Carrying Value		$ 274,600,000	$ 274,300,000
Fair Value		274,300,000	271,700,000
Line of Credit \| Revolving credit facility \| Fair Value, Inputs, Level 2
Debt Instrument [Line Items]
Carrying Value		0	0
Fair Value		0	0
Line of Credit \| Revolving credit facility \| The Acadian Credit Agreement
Debt Instrument [Line Items]
Face amount		140,000,000
Maximum borrowing capacity				$ 140,000,000
Line of Credit \| Revolving credit facility \| The Acadian Credit Agreement \| Fair Value, Inputs, Level 2
Debt Instrument [Line Items]
Carrying Value		0	0
Fair Value		0	0
Line of Credit \| Revolving credit facility \| Revolving Credit Agreement \| Subsequent Event
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 175,000,000
Senior notes \| 4.80% Senior Notes Due July 27, 2026
Debt Instrument [Line Items]
Face amount		$ 275,000,000
Interest rate		4.80%
Senior notes \| 4.80% Senior Notes Due July 27, 2026 \| Fair Value, Inputs, Level 2
Debt Instrument [Line Items]
Carrying Value		$ 274,600,000	274,300,000
Fair Value		$ 274,300,000	$ 271,700,000

Face (par) amount of debt instrument at time of issuance.

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Acadian Asset Management Inc. 10-Q