CONSOLIDATED STATEMENTS OF INCOME (Consolidated Legg Mason Group [Member], USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Legg Mason Group [Member]
Investment advisory fees
Separate accounts	$ 196,019	$ 204,214	$ 400,812	$ 405,186
Funds	376,835	357,491	776,979	710,190
Performance fees	9,984	19,505	28,598	42,279
Distribution and service fees	85,774	92,314	177,838	188,628
Other	1,285	1,270	2,778	2,676
Total operating revenues	669,897	674,794	1,387,005	1,348,959
Operating Expenses
Compensation and benefits	257,651	284,909	558,003	550,983
Transition-related compensation	12,346	10,974	23,741	13,687
Total compensation and benefits	269,997	295,883	581,744	564,670
Distribution and servicing	160,391	165,832	341,147	350,534
Communications and technology	41,571	39,314	82,072	79,290
Occupancy	35,700	33,492	68,938	67,167
Amortization of intangible assets	5,504	5,749	11,082	11,477
Other	49,882	46,625	94,804	85,145
Total operating expenses	563,045	586,895	1,179,787	1,158,283
Operating Income	106,852	87,899	207,218	190,676
Other Non-Operating Income (Expense)
Interest income	2,982	2,170	6,037	3,985
Interest expense	(21,636)	(24,449)	(43,997)	(47,250)
Other income (expense)	(35,502)	33,189	(32,099)	25,898
Other non-operating income (expense) of consolidated investment vehicles, net	3,081	4,499	8,183	2,106
Total other non-operating income (expense)	(51,075)	15,409	(61,876)	(15,261)
Income Before Income Tax (Benefit) Provision	55,777	103,308	145,342	175,415
Income tax (benefit) provision	(1,606)	26,720	26,261	53,784
Net Income	57,383	76,588	119,081	121,631
Less: Net income (loss) attributable to noncontrolling interests	719	1,253	2,465	(1,635)
Net Income Attributable to Legg Mason, Inc.	$ 56,664	$ 75,335	$ 116,616	$ 123,266
Net Income per Share Attributable to Legg Mason, Inc. Common Shareholders:
Basic (in dollars per share)	$ 0.39	$ 0.50	$ 0.80	$ 0.79
Diluted (in dollars per share)	$ 0.39	$ 0.50	$ 0.80	$ 0.79
Weighted Average Number of Shares Outstanding:
Basic (in shares)	143,877	151,416	146,529	155,746
Diluted (in shares)	143,931	151,940	146,625	156,327
Dividends Declared per Share (in dollars per share)	$ 0.08	$ 0.04	$ 0.16	$ 0.08