CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net income	$ 313,331	$ 252,998	$ 150,952
Adjustments to reconcile net income to net cash provided by operating activities:
Write-down of impaired assets	7,900		42,373
Depreciation and amortization	14,754	13,681	15,093
Amortization of deferred sales commissions	64,380	57,931	53,863
Share-based compensation	54,144	53,179	49,993
Excess tax benefits from share-based payment arrangements	(19,135)	(12,992)	(6,791)
Gain on sale of available for sale investment securities	(5,146)	(14,417)	(3,163)
Net purchases and sales or maturities of trading securities	(38,662)	(25,959)	(27,470)
Gain on trading securities	(2,350)	(3,840)	(5,470)
Loss on sale and retirement of property and equipment	1,774	761	5,326
Capital gains and dividends reinvested		(268)
Deferred income taxes	728	(2,982)	(6,236)
Changes in assets and liabilities:
Cash and cash equivalents - restricted	44,824	(28,439)	(42,812)
Other receivables	(75,428)	(5,690)	(29,422)
Payable to investment companies for securities and payable to customers	17,283	24,818	63,828
Receivables from funds and separate accounts	(2,643)	(2,581)	(2,044)
Other assets	(5,568)	(1,139)	2,872
Deferred sales commissions	(40,958)	(68,470)	(54,430)
Accounts payable and payable to third party brokers	21,640	8,613	6,969
Other liabilities	(5,826)	41,712	20,004
Net cash provided by operating activities	345,042	286,916	233,435
Cash flows from investing activities:
Purchases of available for sale investment securities	(166,302)	(241,644)	(51,676)
Proceeds from sales and maturities of available for sale investment securities	164,247	262,171	49,809
Fund adoption transaction	(1,447)
Additions to property and equipment	(35,606)	(16,905)	(15,262)
Disposition of companies		22,000
Net cash provided by (used in) investing activities	(39,108)	25,622	(17,129)
Cash flows from financing activities:
Dividends paid	(115,263)	(96,018)	(171,267)
Repurchase of common stock	(131,030)	(72,132)	(48,688)
Exercise of stock options		135	105
Excess tax benefits from share-based payment arrangements	19,135	12,992	6,791
Net cash used in financing activities	(227,158)	(155,023)	(213,059)
Net increase in cash and cash equivalents	78,776	157,515	3,247
Cash and cash equivalents at beginning of year, including discontinued operations	487,845	330,330	327,083
Cash and cash equivalents at end of year	566,621	487,845	330,330
Less cash and cash equivalents of discontinued operations at end of year			2,303
Cash and cash equivalents of continuing operations at end of year	566,621	487,845	328,027
Cash paid for:
Income taxes (net)	165,189	124,196	98,181
Interest	$ 10,291	$ 10,297	$ 10,286