Noncontrolling interest - Holdings Share Issuances & Cancellations (Details)	9 Months Ended
Sep. 30, 2020 shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	0
Change in APAM economic ownership Interest in Artisan Partners Holdings LP (as a percent)	2.00%
Delivery of Shares Underlying RSUs (in shares)	24,233
Restricted share award net share settlement (in shares)	(126,971)
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Forfeitures of Holdings GP Units from Employee Terminations (in shares)	0
Artisan Partners Holdings LP
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending balance	78.00%
Follow On Offering
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	0
Class A Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Delivery of Shares Underlying RSUs (in shares)	24,233
Restricted share award net share settlement (in shares)	(126,971)
Ending balance (in shares)	61,425,521
Class A Common Stock \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Forfeitures of Holdings GP Units from Employee Terminations (in shares)	(2,420,124)
Class A Common Stock \| Follow On Offering
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	1,802,326
Limited Partnership Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	21,372,029
Holdings common unit exchanges (in shares)	(2,420,124)
Delivery of Shares Underlying RSUs (in shares)	0
Restricted share award net share settlement (in shares)	0
Forfeitures of Holdings GP Units from Employee Terminations (in shares)	0
Ending balance (in shares)	17,149,579
Limited Partnership Units \| Follow On Offering
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	1,802,326
Capital Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	77,801,854
Holdings common unit exchanges (in shares)	0
Holdings of common unit exchanges, APAM ownership percentage	3.00%
Change in APAM economic ownership Interest in Artisan Partners Holdings LP (as a percent)	0.00%
Restricted share award net share settlement (in shares)	(126,971)
Forfeitures of Holdings GP Units from Employee Terminations (in shares)	(40,101)
Ending balance (in shares)	78,575,100
Capital Units \| Artisan Partners Holdings LP
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	73.00%
Ending balance	78.00%
Restricted Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	916,085
Restricted Stock \| Class A Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	916,085
Restricted Stock \| Limited Partnership Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	0
Restricted Stock \| Capital Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	916,085
Change in APAM economic ownership Interest in Artisan Partners Holdings LP (as a percent)	0.00%
Capital Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Change in APAM economic ownership Interest in Artisan Partners Holdings LP (as a percent)	0.00%

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