Fair Values of Assets and Liabilities (Tables) - Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member]

3 Months Ended

Jun. 30, 2015

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurements, Recurring and Nonrecurring [Table Text Block]



	As of June 30, 2015
	Quoted prices in active markets (Level 1)			Significant other observable inputs (Level 2)			Significant unobservable inputs (Level 3)			Total
Assets:
Cash equivalents⁽¹⁾:
Money market funds	$	254,195		$	—		$	—		$	254,195
Time deposits and other	—			34,702			—			34,702
Total cash equivalents	254,195			34,702			—			288,897
Current investments:
Trading investments relating to long-term incentive compensation plans⁽²⁾	110,102			655			—			110,757
Trading investments of proprietary fund products and other trading investments⁽³⁾	205,504			87,499			191			293,194
Equity method investments relating to long-term incentive compensation plans, proprietary fund products and other investments⁽⁴⁾⁽⁵⁾	2,181			13,536			—			15,717
Total current investments	317,787			101,690			191			419,668
Investments in partnerships, LLCs and other⁽⁶⁾	1,059			—			11,907			12,966
Equity method investments in partnerships and LLCs⁽⁴⁾⁽⁶⁾	—			—			41,562			41,562
Derivative assets⁽⁷⁾	4,091			4,487			—			8,578
Other investments⁽⁶⁾	—			—			76			76
Total	$	577,132		$	140,879		$	53,736		$	771,747
Liabilities:
Long-term debt⁽⁸⁾	$	—		$	(254,487	)	$	—		$	(254,487	)
Contingent consideration liabilities⁽⁹⁾	—			—			(92,744		)	(92,744		)
Derivative liabilities⁽⁷⁾	(61		)	—			—			(61		)
Total	$	(61	)	$	(254,487	)	$	(92,744	)	$	(347,292	)



	As of March 31, 2015
	Quoted prices in active markets (Level 1)			Significant other observable inputs (Level 2)			Significant unobservable inputs (Level 3)			Total
Assets:
Cash equivalents⁽¹⁾:
Money market funds	$	353,265		$	—		$	—		$	353,265
Time deposits and other	—			47,035			—			47,035
Total cash equivalents	353,265			47,035			—			400,300
Current investments:
Trading investments relating to long-term incentive compensation plans⁽²⁾	80,529			—			—			80,529
Trading investments of proprietary fund products and other trading investments⁽³⁾	269,647			88,201			186			358,034
Equity method investments relating to long-term incentive compensation plans, proprietary fund products and other investments⁽⁴⁾⁽⁵⁾	2,148			14,024			—			16,172
Total current investments	352,324			102,225			186			454,735
Investments in partnerships, LLCs and other⁽⁶⁾	—			—			14,511			14,511
Equity method investments in partnerships and LLCs⁽⁴⁾⁽⁶⁾	—			—			48,344			48,344
Derivative assets⁽⁷⁾	580			5,462			—			6,042
Other investments⁽⁶⁾	—			—			77			77
Total	$	706,169		$	154,722		$	63,118		$	924,009
Liabilities:
Long-term debt⁽⁸⁾	$	—		$	(255,462	)	$	—		$	(255,462	)
Contingent consideration liability⁽⁹⁾	—			—			(110,784		)	(110,784		)
Derivative liabilities⁽⁷⁾	(8,665		)	—			—			(8,665		)
Total	$	(8,665	)	$	(255,462	)	$	(110,784	)	$	(374,911	)

(1)

Cash equivalents include highly liquid investments with original maturities of 90 days or less. Cash investments in actively traded money market funds are measured at NAV and are classified as Level 1. Cash investments in time deposits and other are measured at amortized cost, which approximates fair value because of the short time between the purchase of the instrument and its expected realization, and are classified as Level 2.


(2)	Primarily mutual funds where there is minimal market risk to the Company as any change in value is primarily offset by an adjustment to compensation expense and related deferred compensation liability.


(3)	Trading investments of proprietary fund products and other trading investments consist of approximately 65% and 35% in equity and debt securities, respectively, as of June 30, 2015, and approximately 63% and 37% in equity and debt securities, respectively, as of March 31, 2015.


(4)	Substantially all of Legg Mason's equity method investments are investment companies which record their underlying investments at fair value. Fair value is measured using Legg Mason's share of the investee's underlying net income or loss, which is predominately representative of fair value adjustments in the investments held by the equity method investee.

(5)

Includes investments under the equity method (which approximate fair value) relating to long-term incentive compensation plans of $8,456 and $8,728 as of June 30, 2015 and March 31, 2015, respectively, and proprietary fund products and other investments of $7,261 and $7,444 as of June 30, 2015 and March 31, 2015, respectively, which are classified as Investment securities in the Consolidated Balance Sheets.


(6)	Amounts are included in Other non-current assets in the Consolidated Balance Sheets for each of the periods presented.


(7)	See Note 11.


(8)	Long-term debt is the sum of the amortized cost of long-term debt and the fair value of an interest rate swap contract designated as a fair value hedge. See Note 7.


(9)	See Note 3.

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]



	Value as of March 31, 2015			Purchases		Sales			Redemptions/ Settlements/ Other			Transfers		Realized and unrealized gains/(losses), net			Value as of June 30, 2015
Assets:
Trading investments of proprietary fund products and other trading investments	$	186		$	—	$	(7	)	$	—		$	—	$	12		$	191
Investments in partnerships, LLCs and other	14,511			—		—			(2,528		)	—		(76		)	11,907
Equity method investments in partnerships and LLCs	48,344			1,243		(6,170		)	(2,432		)	—		577			41,562
Other investments	77			—		—			—			—		(1		)	76
	$	63,118		$	1,243	$	(6,177	)	$	(4,960	)	$	—	$	512		$	53,736
Liabilities:
Contingent consideration liabilities	$	(110,784	)	$	—	$	—		$	22,765		$	—	$	(4,725	)	$	(92,744	)



	Value as of March 31, 2014			Purchases			Sales			Redemptions/Settlements/ Other			Transfers		Realized and unrealized gains/(losses), net			Value as of June 30, 2014
Assets:
Trading investments of proprietary fund products and other trading investments	$	190		$	—		$	(10	)	$	—		$	—	$	(1	)	$	179
Investments in partnerships, LLCs and other	21,586			—			—			—			—		68			21,654
Equity method investments in partnerships and LLCs	62,973			968			(5,848		)	(564		)	—		92			57,621
Other investments	90			—			—			—			—		2			92
	$	84,839		$	968		$	(5,858	)	$	(564	)	$	—	$	161		$	79,546
Liabilities:
Contingent consideration liability	$	(29,553	)	$	(14,670	)	$	—		$	—		$	—	$	(1,061	)	$	(45,284	)

Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Table Text Block]



		Fair Value Determined Using NAV						As of June 30, 2015
Category of Investment	Investment Strategy	June 30, 2015			March 31, 2015			Unfunded Commitments		Remaining Term
Funds-of-hedge funds	Global macro, fixed income, long/short equity, natural resources, systematic, emerging market, European hedge	$	25,539	(1)	$	23,787		n/a		n/a
Hedge funds	Fixed income - developed market, event driven, fixed income - hedge, relative value arbitrage, European hedge	13,623			14,515			$	20,000	n/a
Private equity funds	Long/short equity	23,411		(2)	23,563			8,534		Up to 10 years
Other	Various	1,108			1,129			n/a		Various ⁽³⁾
Total		$	63,681	(4)	$	62,994	(4)	$	28,534

n/a-not applicable


(1)	Liquidation restrictions: 1% daily redemption, 9% monthly redemption and 90% quarterly redemption as of June 30, 2015.


(2)	Liquidations are expected over the remaining term.


(3)	Of this balance, 23% has a remaining term of less than one year and 77% has a remaining term of 17 years.


(4)	Comprised of 1%, 39%, and 60% of Level 1, Level 2, and Level 3 assets, respectively, as of June 30, 2015 and 38% and 62% of Level 2 and Level 3 assets, respectively, as of March 31, 2015.