CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS UNAUDITED (USD $)	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Operating activities
Net income	$ 57,299,000	$ 50,592,000
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Equity in net gains from partnerships	(2,884,000)	1,418,000
Depreciation and amortization	336,000	406,000
Stock based compensation expense	3,397,000	29,000
Deferred income taxes	(1,512,000)	1,421,000
Tax benefit from exercise of stock options	349,000	16,000
Foreign currency translation gain/(loss)	30,000	(48,000)
Other-than-temporary loss on available for sale securities	69,000	14,000
Fair value of donated securities	1,480,000	277,000
Gains on sales of available for sale securities	(3,163,000)	(10,446,000)
Accretion of zero coupon debentures	440,000	645,000
Loss on extinguishment of debt	74,000	137,000
(Increase) decrease in assets:
Investments in trading securities	9,899,000	2,538,000
Investments in partnerships:
Contributions to partnerships	(12,098,000)	(8,221,000)
Distributions from partnerships	3,077,000	9,818,000
Receivable from brokers	(9,484,000)	10,986,000
Investment advisory fees receivable	19,278,000	14,189,000
Income tax receivable and deferred tax assets	(632,000)	605,000
Other assets	(4,739,000)	2,246,000
Increase (decrease) in liabilities:
Payable to brokers	9,094,000	640,000
Income taxes payable and deferred tax liabilities	(4,707,000)	1,551,000
Compensation payable	34,240,000	49,108,000
Mandatorily redeemable noncontrolling interests	(16,000)	(20,000)
Accrued expenses and other liabilities	(405,000)	5,530,000
Total adjustments	42,123,000	82,839,000
Net cash provided by operating activities	99,422,000	133,431,000
Investing activities
Purchases of available for sale securities	(5,354,000)	(3,953,000)
Proceeds from sales of available for sale securities	6,518,000	21,978,000
Return of capital on available for sale securities	561,000	625,000
Net cash provided by investing activities	1,725,000	18,650,000
Financing activities
Contributions from redeemable noncontrolling interests	16,096,000	2,875,000
Redemptions of redeemable noncontrolling interests	(470,000)	(13,394,000)
Repayments of Senior Debt, Total	0	(99,000,000)
Payments to Noncontrolling Interests	0	(524,000)
Proceeds from exercise of stock options	1,637,000	76,000
Repurchase of zero coupon subordinated debentures	(612,000)	(1,119,000)
Dividends paid	(3,050,000)	(2,570,000)
Purchase of treasury stock	(17,698,000)	(6,275,000)
Net cash provided used in financing activities	(4,097,000)	(119,931,000)
Effect of exchange rates on cash and cash equivalents	(11,000)	18,000
Net increase in cash and cash equivalents	97,039,000	32,168,000
Cash and cash equivalents at beginning of period	210,451,000	190,608,000
Cash and cash equivalents at end of period	307,490,000	222,776,000
Supplemental disclosures of cash flow information:
Cash paid for interest	3,539,000	6,262,000
Cash paid for taxes	$ 37,020,000	$ 25,165,000