Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2014 Consolidated Legg Mason, Inc.	Mar. 31, 2013 Consolidated Legg Mason, Inc.	Mar. 31, 2012 Consolidated Legg Mason, Inc.
Cash Flows from Operating Activities
Net Income (Loss)	$ 281,836	$ (359,748)	$ 231,031
2.5% Convertible Senior Notes:
Allocation of repurchase payment	0	(216,038)	0
Loss on extinguishment	0	68,975	0
Adjustments to reconcile Net Income (Loss) to net cash provided by operations:
Impairment of intangible assets	0	734,000	0
Depreciation and amortization	62,845	87,848	93,795
Imputed interest for 2.5% Convertible Senior Notes	0	5,839	39,077
Accretion and amortization of securities discounts and premiums, net	3,037	3,295	4,552
Stock-based compensation	66,488	58,983	48,735
Net (gains) losses on investments	(26,805)	(43,684)	(1,714)
Net losses (gains) of consolidated investment vehicles	(643)	5,358	(6,711)
Deferred income taxes	118,430	(157,355)	49,192
Other	3,276	1,725	(12,191)
Decrease (increase) in assets:
Investment advisory and related fees receivable	(2,061)	(11,045)	31,790
Net (purchases) sales of trading and other current investments	(44,293)	189,347	(40,020)
Other receivables	14,105	(9,712)	1,432
Other assets	(24,042)	(1,605)	1,810
Other assets of consolidated investment vehicles	(62,916)	(14,378)	53,720
Increase (decrease) in liabilities:
Accrued compensation	76,968	(54,964)	42,763
Deferred compensation	(7,191)	(530)	(35,148)
Accounts payable and accrued expenses	319	8,690	(11,147)
Other liabilities	(18,310)	3,112	28,135
Other liabilities of consolidated investment vehicles	(3,719)	5,219	(22,332)
CASH PROVIDED BY OPERATING ACTIVITIES	437,324	303,332	496,769
Cash Flows From Investing Activities
Payments for fixed assets	(40,452)	(38,351)	(31,822)
Acquisitions/dispositions	1,351	(55,277)	3,060
Change in restricted cash	(5,801)	(7,245)	11,221
Purchases of investment securities	(4,335)	(5,787)	(6,493)
Proceeds from sales and maturities of investment securities	4,306	5,272	6,197
Purchases of investments by consolidated investment vehicles	(17,328)	(98,374)	(141,727)
Proceeds from sales and maturities of investments by consolidated investment vehicles	199,886	188,739	161,894
Cash Provided by (Used In) Investing Activities	137,627	(11,023)	2,330
Cash Flows From Financing Activities
Repayment of short-term borrowings	0	(250,000)	0
Repayment of 2.5% Convertible Senior Notes, net of operating allocation	0	(1,040,212)	(1,014)
Repayment of long-term debt	(500,439)	(9,006)	0
Repayment of long term debt of Consolidated Investment Vehicles	(133,047)	(75,561)	0
Proceeds from issuance of long-term debt	393,740	1,143,246	0
Debt issuance costs	(3,940)	(10,289)	0
Issuance of common stock for stock-based compensation	25,603	1,986	4,538
Employee Tax Withholdings by settlement of net share transaction	(19,464)	(11,302)	0
Repurchase of common stock	(359,996)	(425,516)	(401,797)
Dividends paid	(61,966)	(55,250)	(43,602)
Net repayments of consolidated investment vehicles	0	0	(18,309)
Net (redemptions/distributions paid to)/subscriptions received from noncontrolling interest holders	20,438	(3,993)	(21,596)
Cash Used In Financing Activities	(639,071)	(735,897)	(481,780)
Effect of Exchange Rate on Cash	(10,894)	(5,639)	(10,974)
Net Increase (Decrease) in Cash and Cash Equivalents	(75,014)	(449,227)	6,345
Cash and Cash Equivalents at Beginning of Period	933,036	1,382,263	1,375,918
Cash and Cash Equivalents at End of Period	858,022	933,036	1,382,263
Income taxes, net of (refunds) payments of $(13,835), $(2,313) and $(12,034), respectively	10,140	32,318	24,552
Interest	$ 44,295	$ 40,262	$ 41,039