Significant Accounting Policies - Additional Information (Details)	3 Months Ended			9 Months Ended
	Sep. 30, 2020 USD ($)		Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) segment		Sep. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)		Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Revenue Recognition
Contract measurement period (in years)				3 years
Cash and Cash Equivalents
Cash	$ 49,235,000	[1]	$ 35,685,000	$ 49,235,000	[1]	$ 35,685,000	$ 33,131,000	$ 52,480,000	[1]	$ 33,783,000	$ 38,099,000
Restricted Cash	1,047,000		1,033,000	1,047,000		1,033,000	$ 1,043,000	1,036,000		$ 1,031,000	$ 1,028,000
Impairment losses recognized	0		0	0		0
Concentration of Credit Risk
Allowance for doubtful accounts receivable	$ 0			$ 0				0
Lease term	12 months			12 months
Business Segments
Number of operating segments (in segments) | segment				1
Income Taxes
Valuation allowance on deferred tax assets	$ 0			$ 0				$ 0
Section 754 election tax deduction period				15 years
Cash savings generated by this election will be distributed to selling and converting shareholders upon realization (in hundredth)	85.00%			85.00%
Percentage of cash tax savings in income tax if realizes company expects to benefit	15.00%			15.00%
Percentage of estimated realizable tax benefit added to liability due under tax receivable agreement	85.00%			85.00%
Cash savings generated by this election will increase additional paid-in capital	15.00%			15.00%
Foreign Currency
Other comprehensive income (loss) associated with foreign currency translation adjustments	$ 295,000		$ (104,000)	$ 73,000		(114,000)
Maximum
Foreign Currency
Other comprehensive income (loss) associated with foreign currency translation adjustments				$ 100,000		$ (100,000)
Equipment | Minimum
Concentration of Credit Risk
Property and equipment, useful life (years)				3 years
Equipment | Maximum
Concentration of Credit Risk
Property and equipment, useful life (years)				7 years

[1] Asset and liability amounts in parentheses represent the aggregated balances at September 30, 2020 and December 31, 2019 attributable to Pzena Investment Management Special Situations, LLC, Pzena U.S. Best Ideas (GP), LLC, and Pzena Global Best Ideas (GP), LLC which were variable interest entities as of September 30, 2020 and December 31, 2019, respectively. Asset and liability amounts in parentheses at September 30, 2020 are also attributable to Pzena Global Focus Value Fund. Asset and liability amounts in parentheses at December 31, 2019 are also attributable to Pzena International Value Service (a series of Pzena Investment Management International, LLC).