Consolidated Company-Sponsored Investment Funds - Change in Carrying Value Associated with Level 3 Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair value measurement Level 3 reconciliation [Abstract]
Balance as of beginning of period	$ 126	$ 114	$ 125	$ 119
Purchases	0	0	0	0
Sales	0	0	0	0
Realized gains (losses), net	0	0	0	0
Unrealized gains (losses), net	1	7	2	2
Balance as of end of period	127	121	127	121
Company-sponsored investment funds
Fair value measurement Level 3 reconciliation [Abstract]
Balance as of beginning of period	210	517	619	854
Deconsolidated funds	0	0	(717)	(135)
Transfers (out) in, net	(202)	(6)	(212)	565
Purchases	0	61	323	107
Sales	(4)	(7)	(7)	(451)
Realized gains (losses), net	0	(7)	3	(21)
Unrealized gains (losses), net	(4)	39	(9)	(323)
Accrued discounts	0	0	0	1
Balance as of end of period	$ 0	$ 597	$ 0	$ 597

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

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-Publisher FASB
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- Definition

Amount of increase (decrease) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of accretion (amortization) of purchase discount (premium) on nonoperating securities.

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