Fair Value (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value of Assets and Liabilities Measured on a Recurring Basis

Valuation of our financial instruments by pricing observability levels as of December 31, 2019 and 2018 was as follows (in thousands):

	Level 1		Level 2		Level 3		NAV Expedient(1)		Other		Total
December 31, 2019:
Money markets	$	126,401	$	—	$	—	$	—	$	—	$	126,401
Securities segregated (U.S. Treasury Bills)	—		1,094,866		—		—		—		1,094,866
Derivatives	939		12,552		—		—		—		13,491
Investments
Equity securities	170,946		8,952		119		314		—		180,331
Long exchange-traded options	6,931		—		—		—		—		6,931
Limited partnership hedge       funds(2)	—		—		—		—		47,361		47,361
Time deposits(3)	—		—		—		—		18,281		18,281
Other investments	5,883		—		—		—		8,007		13,890
Total investments	183,760		8,952		119		314		73,649		266,794
Total assets measured at fair value	$	311,100	$	1,116,370	$	119	$	314	$	73,649	$	1,501,552
Securities sold not yet purchased
Short equities – corporate	$	17,809	$	—	$	—	$	—	$	—	$	17,809
Short exchange-traded options	12,348		—		—		—		—		12,348
Derivatives	871		18,388		—		—		—		19,259
Contingent payment arrangements	—		—		22,911		—		—		22,911
Total liabilities measured at fair value	$	31,028	$	18,388	$	22,911	$	—	$	—	$	72,327

	Level 1		Level 2		Level 3		NAV Expedient(1)		Other		Total
December 31, 2018:
Money markets	$	102,888	$	—	$	—	$	—	$	—	$	102,888
Securities segregated (U.S. Treasury Bills)	—		1,169,554		—		—		—		1,169,554
Derivatives	1,594		15,485		—		—		—		17,079
Investments
U.S. Treasury Bills	—		392,424		—		—		—		392,424
Equity securities	209,414		8,372		142		315		—		218,243
Long exchange-traded options	2,568		—		—		—		—		2,568
Limited partnership hedge       funds(2)	—		—		—		—		80,699		80,699
Time deposits(3)	—		—		—		—		8,783		8,783
Other investments	4,269		—		—		—		7,358		11,627
Total investments	216,251		400,796		142		315		96,840		714,344
Total assets measured at fair value	$	320,733	$	1,585,835	$	142	$	315	$	96,840	$	2,003,865
Securities sold not yet purchased
Short equities – corporate	$	4,841	$	—	$	—	$	—	$	—	$	4,841
Short exchange-traded options	3,782		—		—		—		—		3,782
Derivatives	2,534		12,288		—		—		—		14,822
Contingent payment arrangements	—		—		7,336		—		—		7,336
Total liabilities measured at fair value	$	11,157	$	12,288	$	7,336	$	—	$	—	$	30,781

⁽¹⁾ Investments measured at fair value using NAV (or its equivalent) as a practical expedient.

⁽²⁾ Investments in equity method investees that are not measured at fair value in accordance with GAAP.

⁽³⁾ Investments carried at amortized cost that are not measured at fair value in accordance with GAAP.

Fair Value Measurement Level 3 Reconciliation

The change in carrying value associated with Level 3 financial instruments carried at fair value, classified as equity securities, is as follows:

	December 31, 2019			December 31, 2018
	(in thousands)
Balance as of beginning of period	$	142		$	1,071
Purchases	—			—
Sales	—			—
Realized gains (losses), net	—			—
Unrealized (losses) gains, net	(23		)	(929		)
Balance as of end of period	$	119		$	142

Schedule of Contingent Payment Arrangements Level 3 Financial Instruments

The change in carrying value associated with Level 3 financial instruments carried at fair value, classified as contingent payment arrangements, is as follows:

	December 31, 2019			December 31, 2018
	(in thousands)
Balance as of beginning of period	$	7,336		$	10,855
Addition	17,384			—
Accretion	2,542			210
Changes in estimates	(3,051		)	(2,429		)
Payments	(1,300		)	(1,300		)
Balance as of end of period	$	22,911		$	7,336