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Investments, Fair Value Disclosure and Other Measurements

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Investments, Measurements Other than Fair Value

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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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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Fair value of obligations arising from derivatives and other contracts sold short.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Fair value of financial and nonfinancial obligations.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Fair value portion of liabilities pertaining to principal and customer trading transactions, or which may be incurred with the objective of generating a profit from short-term fluctuations in price as part of an entity's market-making, hedging and proprietary trading. Examples include, but are not limited to, short positions in securities, derivatives and commodities.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair Value - Valuation of Financial Instruments by Pricing Observability Levels (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments
Investments, other measurements	$ 73,649	$ 96,840
Securities sold not yet purchased
Contingent payment arrangements	17,384	0	$ 0
Other investments
Investments
Investments, other measurements	8,007	7,358
Hedge funds
Investments
Investments, other measurements	47,361	80,699
Time deposits
Investments
Investments, other measurements	18,281	8,783
Recurring
Assets, Fair Value Disclosure [Abstract]
Money markets	126,401	102,888
Securities segregated (U.S. Treasury Bills)	1,094,866	1,169,554
Derivatives	13,491	17,079
Investments
Total investments measured at fair value and other measurements	266,794	714,344
Total assets measured at fair value and other measurements	1,501,552	2,003,865
Securities sold not yet purchased
Short equities – corporate	17,809	4,841
Short exchange-traded options	12,348	3,782
Derivatives	19,259	14,822
Contingent payment arrangements	22,911	7,336
Total liabilities measured at fair value	72,327	30,781
Recurring \| Level 1
Assets, Fair Value Disclosure [Abstract]
Money markets	126,401	102,888
Securities segregated (U.S. Treasury Bills)	0	0
Derivatives	939	1,594
Investments
Total investments	183,760	216,251
Total assets measured at fair value	311,100	320,733
Securities sold not yet purchased
Short equities – corporate	17,809	4,841
Short exchange-traded options	12,348	3,782
Derivatives	871	2,534
Contingent payment arrangements	0	0
Total liabilities measured at fair value	31,028	11,157
Recurring \| Level 2
Assets, Fair Value Disclosure [Abstract]
Money markets	0	0
Securities segregated (U.S. Treasury Bills)	1,094,866	1,169,554
Derivatives	12,552	15,485
Investments
Total investments	8,952	400,796
Total assets measured at fair value	1,116,370	1,585,835
Securities sold not yet purchased
Short equities – corporate	0	0
Short exchange-traded options	0	0
Derivatives	18,388	12,288
Contingent payment arrangements	0	0
Total liabilities measured at fair value	18,388	12,288
Recurring \| Level 3
Assets, Fair Value Disclosure [Abstract]
Money markets	0	0
Securities segregated (U.S. Treasury Bills)	0	0
Derivatives	0	0
Investments
Total investments	119	142
Total assets measured at fair value	119	142
Securities sold not yet purchased
Short equities – corporate	0	0
Short exchange-traded options	0	0
Derivatives	0	0
Contingent payment arrangements	22,911	7,336
Total liabilities measured at fair value	22,911	7,336
Recurring \| NAV Expedient
Investments
Fair value of private equity investment	314	315
Recurring \| U.S. Treasury Bills
Investments
Investments		392,424
Recurring \| U.S. Treasury Bills \| Level 1
Investments
Investments		0
Recurring \| U.S. Treasury Bills \| Level 2
Investments
Investments		392,424
Recurring \| U.S. Treasury Bills \| Level 3
Investments
Investments		0
Recurring \| Equity securities
Investments
Investments	180,331	218,243
Recurring \| Equity securities \| Level 1
Investments
Investments	170,946	209,414
Recurring \| Equity securities \| Level 2
Investments
Investments	8,952	8,372
Recurring \| Equity securities \| Level 3
Investments
Investments	119	142
Recurring \| Equity securities \| NAV Expedient
Investments
Fair value of private equity investment	314	315
Recurring \| Other investments
Investments
Investments, other measurements		11,627
Total investments measured at fair value and other measurements	13,890
Recurring \| Other investments \| Level 1
Investments
Investments, other measurements		4,269
Total investments	5,883
Recurring \| Long exchange-traded options \| Exchange-traded options
Investments
Investments	6,931	2,568
Recurring \| Long exchange-traded options \| Exchange-traded options \| Level 1
Investments
Investments	6,931	2,568
Recurring \| Long exchange-traded options \| Exchange-traded options \| Level 2
Investments
Investments	0	0
Recurring \| Long exchange-traded options \| Exchange-traded options \| Level 3
Investments
Investments	0	0
Recurring \| Hedge funds
Investments
Investments, other measurements	47,361	80,699
Recurring \| Time deposits
Investments
Investments, other measurements	$ 18,281	$ 8,783