VIE Consolidated Balance Sheet Detail (Details) - USD ($) $ in Thousands		Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Mar. 31, 2015
Variable Interest Entity
REDEEMABLE NONCONTROLLING INTERESTS		$ 722,562	$ 175,785	$ 55,513	$ 45,520
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity
Current Assets	[1]	173,895	110,631
Non-current Assets	[1]	7,601	84
TOTAL ASSETS	[1]	181,496	110,715
Current Liabilities	[1]	6,778	4,548
Non-current Liabilities	[1]	0	0
TOTAL LIABILITIES	[1]	6,778	4,548
REDEEMABLE NONCONTROLLING INTERESTS	[1]	153,877	94,027
Total Stockholders' Equity	[1]	20,841	12,140
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	[1]	181,496	110,715
Consolidated Legg Mason, Inc.
Variable Interest Entity
Current Assets		1,702,319	2,385,044
Non-current Assets		6,594,274	5,135,402
TOTAL ASSETS		8,296,593	7,520,446
Current Liabilities		1,116,111	841,553
Non-current Liabilities		2,340,350	2,267,343
TOTAL LIABILITIES		3,456,461	3,108,896
REDEEMABLE NONCONTROLLING INTERESTS		722,562	175,785
Total Stockholders' Equity		4,117,570	4,235,765	$ 4,522,206
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY		8,296,593	7,520,446
Consolidated Entity Excluding Variable Interest Entities (VIE) [Member]
Variable Interest Entity
Current Assets	[1]	1,587,872	2,288,080
Non-current Assets	[1]	6,586,673	5,135,318
TOTAL ASSETS	[1]	8,174,545	7,423,398
Current Liabilities	[1]	1,109,333	837,031
Non-current Liabilities	[1]	2,340,350	2,267,343
TOTAL LIABILITIES	[1]	3,449,683	3,104,374
REDEEMABLE NONCONTROLLING INTERESTS	[1]	607,179	81,649
Total Stockholders' Equity	[1]	4,117,683	4,237,375
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	[1]	8,174,545	7,423,398
Consolidation, Eliminations [Member]
Variable Interest Entity
Current Assets		(59,448)	(13,667)
Non-current Assets		0	0
TOTAL ASSETS		(59,448)	(13,667)
Current Liabilities		0	(26)
Non-current Liabilities		0	0
TOTAL LIABILITIES		0	(26)
REDEEMABLE NONCONTROLLING INTERESTS		(38,494)	109
Total Stockholders' Equity		(20,954)	(13,750)
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY		$ (59,448)	$ (13,667)

[1] Other represents consolidated sponsored investment vehicles that are not designated as CIVs.