Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash Flows From Operating Activities
Net Income	$ 57,690	$ 107,371	$ 72,022
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Net (Gains) Losses on Investments, Marketable Securities and Contingent Consideration	5,517	(2,505)	(2,172)
Equity Method Investments	2,818	4,476	(1,454)
Equity-Based and Other Deferred Compensation	207,533	111,771	121,608
Impairment of Goodwill	28,500	0	0
Depreciation, Amortization and Accretion	29,636	18,773	16,699
Bad Debt Expense	1,314	1,027	2,099
Adjustment to Tax Receivable Agreements	0	0	(6,905)
Deferred Taxes	(3,627)	14,315	20,058
Decrease (Increase) in Operating Assets:
Marketable Securities	556	550	234
Financial Instruments Owned and Pledged as Collateral at Fair Value	46,018	(54,032)	65,045
Securities Purchased Under Agreements to Resell	4,726	10,303	(19,578)
Accounts Receivable	(46,442)	(51,166)	1,460
Receivable from Employees and Related Parties	(3,937)	(6,646)	(4,542)
Other Assets	(3,903)	(7,651)	(19,945)
(Decrease) Increase in Operating Liabilities:
Accrued Compensation and Benefits	51,732	27,251	12,435
Accounts Payable and Accrued Expenses	5,418	6,231	258
Securities Sold Under Agreements to Repurchase	(50,803)	43,771	(45,543)
Payables to Employees and Related Parties	8,704	(2,601)	4,451
Taxes Payable	17,850	(2,650)	(15,591)
Other Liabilities	(2,449)	(2,616)	(1,925)
Net Cash Provided by Operating Activities	356,851	215,972	198,714
Cash Flows From Investing Activities
Investments Purchased	(819)	(10,944)	(3,012)
Distributions of Private Equity Investments	6,821	672	1,300
Marketable Securities:
Proceeds from Sales and Maturities	32,318	34,719	31,106
Purchases	(39,101)	(28,760)	(35,187)
Cash Paid for Acquisitions and Deconsolidation of Atalanta Sosnoff, net of Cash Acquired	(5,647)	42,869	218
Proceeds from Sale of Business	0	0	1,198
Loans Receivable	(3,500)	0	0
Purchase of Furniture, Equipment and Leasehold Improvements	(16,189)	(13,521)	(4,487)
Net Cash Provided by (Used in) Investing Activities	(26,117)	25,035	(8,864)
Cash Flows From Financing Activities
Issuance of Noncontrolling Interests	594	2,135	3,589
Distributions to Noncontrolling Interests	(23,723)	(10,655)	(18,950)
Payments Under Tax Receivable Agreement	(11,045)	(9,086)	(7,651)
Cash Paid for Deferred and Contingent Consideration	0	(2,255)	(3,396)
Short-Term Borrowing	45,000	75,000	0
Repayment of Short-Term Borrowing	(45,000)	(75,000)	0
Proceeds from Warrant Exercises	6,416	0	0
Purchase of Treasury Stock and Noncontrolling Interests	(160,733)	(156,242)	(102,277)
Excess Tax Benefits Associated with Equity-Based Awards	10,820	35,262	8,979
Dividends - Class A Stockholders	(46,132)	(38,754)	(30,090)
Net Cash Provided by (Used in) Financing Activities	(223,803)	(179,595)	(149,796)
Effect of Exchange Rate Changes on Cash	(10,327)	(7,705)	(1,032)
Net Increase in Cash and Cash Equivalents	96,604	53,707	39,022
Cash and Cash Equivalents-Beginning of Period	352,160	298,453	259,431
Cash and Cash Equivalents-End of Period	448,764	352,160	298,453
SUPPLEMENTAL CASH FLOW DISCLOSURE
Payments for Interest	16,035	13,725	12,807
Payments for Income Taxes	47,820	18,283	57,178
Increase (Decrease) in Fair Value of Redeemable Noncontrolling Interest	(1,331)	3,261	(12,985)
Dividend Equivalents Issued	6,514	6,038	5,989
Receipt of Securities in Settlement of Accounts Receivable	1,079	2,083	2,278
Contingent Consideration Accrued	13,699	1,979	0
Value of Noncash Assets Deconsolidated	2,053	0	0
Value of Liabilities Deconsolidated	2,074	0	0
Decrease in Redeemable Noncontrolling Interest	2,683	0	0
Decrease in Noncontrolling Interest	16,090	0	0
Decrease in Goodwill	27,274	0	0
Decrease in Intangible Assets	13,924	0	0
Notes Reduction	118,347	0	0
Purchase of Treasury Stock in Exchange for Notes Issuance and Warrant Proceeds	123,673	0	0
Settlement of Contingent Consideration	0	7,232	2,494
Purchase of Noncontrolling Interest	0	7,100	0
Reclassification from Redeemable Noncontrolling Interest to Noncontrolling Interest	0	27,477	0
Shares and LP Units Issued as Consideration for Acquisitions and Investments	0	79,576	0
Assets Acquired in Acquisitions	0	106,848	0
Liabilities Assumed in Acquisitions	0	64,864	0
Notes Exchanged for Equity in Subsidiary	$ 0	$ 0	$ 1,042