Accumulated Other Comprehensive Income (Loss), Debt Securities, Available For Sale Securities Adjustment Tax

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- Definition

Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e681-108580

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
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- Definition

Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Publisher FASB
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-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
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Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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Amount of long-term investments classified as other.

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-Topic 944
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrealized gain (loss) on investment.

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Marketable Securities (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
Marketable Securities (Narrative) (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Schedule of Investments [Line Items]
Net unrealized gains (losses) of available-for-sale debt securities	$ 673,000		$ 673,000		$ 1,551,000
Unrealized gains (losses) during the period, income tax expense (benefit)	201,000		201,000		464,000
Available-for-sale securities, gross realized gains			0	$ 0
Mutual funds and equities, gross realized gains			714,000	254,000
Mutual funds and equities, gross realized loss			65,000	250,000
Other long-term investments	39,872,000		39,872,000		98,433,000
Securities owned	31,770,000		31,770,000		34,064,000
Cash Equivalents
Schedule of Investments [Line Items]
Cash equivalents at fair value	453,628,000		453,628,000		462,624,000
Available-for-sale debt securities
Schedule of Investments [Line Items]
Available-for-sale securities, gross realized losses			861,000	582,000
Investment Funds Sponsored by LSV
Schedule of Investments [Line Items]
Other long-term investments	6,893,000		6,893,000		$ 6,166,000
Unrealized gain (loss) on investments	$ (39,000)	$ 458,000	$ 727,000	$ (781,000)