Consolidated and Combined Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities
Net income (loss)	$ 141,865	$ 120,217	$ 32,555
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Bad debt expense	(277)	1,213	1,450
Depreciation and amortization	3,183	2,635	2,268
(Income) loss from equity method investments	(5,076)	(4,476)	2,185
Equity-based compensation	77,050	46,131	119,756
Deferred tax provision	(1,014)	796	(753)
Other	2,204	540	3,235
Changes in assets and liabilities:
Accounts receivable	5,536	(7,993)	4,604
Other receivables	3,562	(5,448)	371
Prepaid expenses and other assets	1,754	(5,166)	1,990
Deferred compensation	167	(3,420)	(2,456)
Compensation payable	10,739	(10,618)	33,601
Accounts payable and accrued expenses	(6,219)	1,751	11,103
Deferred revenue	(4,018)	1,855	(1,682)
Dividends received	1,416	4,415
Other liabilities	584	(130)	684
Net cash provided by (used in) operating activities	231,456	142,302	208,911
Cash flows from investing activities
Purchase of investments	(120,906)	(157,981)	(130,994)
Proceeds from sales of investments	126,000	160,001	157,235
Return of capital from equity method investments	11	254
Investment in equity method investments			(4,445)
Note payments received from employees			831
Notes issued to employees	(852)		(119)
Purchase of equipment and leasehold improvements	(2,870)	(3,996)	(3,888)
Change in restricted cash	53	(18)	(81)
Net cash provided by (used in) investing activities	1,436	(1,740)	18,539
Cash flows from financing activities
Dividends and distributions	(154,703)	(80,909)	(123,223)
Purchase of treasury stock	(3,314)	(7,616)
Payments under tax receivable agreement		(1,587)
Excess tax benefits from equity-based compensation	118	462
Class A partnership units and other equity purchased		(90)
Pre-offering distribution to partners			(195,017)
IPO related proceeds (net of $10,316 of offering costs)			163,682
Distributions of IPO proceeds to partners			(139,429)
Other cash contributions from (distributions to) Parent			(34,730)
Cash proceeds from issuance of Class B common stock			500
Other			(938)
Net cash provided by (used in) financing activities	(157,899)	(89,740)	(329,155)
Effect of exchange rate fluctuations on cash and cash equivalents	(4,089)	(744)	(3,375)
Net increase (decrease) in cash and cash equivalents	70,904	50,078	(105,080)
Cash and cash equivalents, beginning of period	248,022	197,944	303,024
Cash and cash equivalents, end of period	318,926	248,022	197,944
Cash paid during the period for:
Income taxes	28,613	26,000	5,649
Other non-cash activity
Dividends declared not paid	68,066
Dividend equivalents issued	23,367	4,130
Class A Partnership Units or other equity converted into Class A Common Stock	835	4,726
Forfeiture of fully-vested Group LP units or other equity units	$ 83	1,075
Non-cash settlement of accounts receivable		$ 635
Initial establishment of deferred tax assets, net of amounts payable under tax receivable agreement			10,854
Increase in deferred tax assets resulting from follow-on offering, net of amounts payable under tax receivable agreement			20,711
Capitalized offering costs paid in prior or subsequent period			1,575
Tax benefit related to settlement of appreciation units			4,308
Establishment of deferred tax asset related to reorganization			3,261
Increase in deferred tax asset related to IPO			1,302
Other non-cash distributions			$ 1,560