Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities
Net income (loss)	$ 132,174	$ 87,137
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Bad debt expense	1,521	124
Depreciation and amortization	2,570	2,359
(Income) loss from equity method investments	(4,565)	(3,897)
Equity-based compensation	72,912	56,313
Deferred tax provision	13,746	(1,931)
Gain on equity method investment	(31,971)
Other	4,067	700
Changes in assets and liabilities:
Accounts receivable	(28,588)	2,763
Other receivables	(4,594)	1,234
Prepaid expenses and other assets	(7,079)	1,432
Deferred compensation	(321)	(841)
Compensation payable	(21,644)	(53,017)
Accounts payable and accrued expenses	(4,864)	(7,664)
Deferred revenue	876	6,324
Dividends received	11,672	804
Other liabilities	(628)	2,075
Net cash provided by (used in) operating activities	135,284	93,915
Cash flows from investing activities
Purchase of investments	(171,764)	(95,919)
Proceeds from sales of investments	88,750	101,000
Return of capital from equity method investments		9
Note payments received from employees	705
Notes issued to employees	(400)	(852)
Purchase of equipment and leasehold improvements	(4,553)	(2,737)
Change in restricted cash	(85)	(30)
Net cash provided by (used in) investing activities	(87,347)	1,471
Cash flows from financing activities
Dividends and distributions	(232,284)	(135,751)
Payments under tax receivable agreement	(5,032)
Payments to settle employee tax obligations on share-based awards	(9,832)	(2,621)
Proceeds from exercise of stock options	5,571
Class A partnership units and other equity purchased	(229)
Net cash provided by (used in) financing activities	(241,806)	(138,372)
Effect of exchange rate fluctuations on cash and cash equivalents	2,543	(2,425)
Net increase (decrease) in cash and cash equivalents	(191,326)	(45,411)
Cash and cash equivalents, beginning of period	318,926	248,022
Cash and cash equivalents, end of period	127,600	202,611
Cash paid during the period for:
Income taxes	26,196	20,609
Dividends paid, declared in the prior year	68,066
Other non-cash activity
Dividend equivalents issued	20,911	10,276
Class A Partnership Units or other equity converted into Class A Common Stock	52,240	$ 783
Cumulative Effect Adjustment upon Adoption of ASU 2016-09	658
Forfeiture of fully-vested Group LP units or other equity units	$ 36