Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Consolidated Legg Mason, Inc.
NET INCOME	$ 64,527	$ (138,610)	$ 196,399	$ 19,248
Other comprehensive income (loss):
Foreign currency translation adjustment	(43,666)	(5,169)	(55,797)	(21,681)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, before Tax	2,493	0	2,493	0
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	0	0	(2,718)	0
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	0	0	(1,708)	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	0	0	2,718	0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	0	0	1,708	0
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	0	0	0	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax	3,568	1,324	(16,483)	4,314
Total other comprehensive income (loss)	(37,605)	(3,845)	(69,787)	(17,367)
COMPREHENSIVE INCOME	26,922	(142,455)	126,612	1,881
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	17,123	16	49,161	(993)
Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member]
Other comprehensive income (loss):
COMPREHENSIVE INCOME ATTRIBUTABLE TO LEGG MASON, INC.	$ 9,799	$ (142,471)	$ 77,451	$ 2,874