Income Taxes (Details 3) (Consolidated Legg Mason, USD $) In Thousands, unless otherwise specified	Mar. 31, 2013		Mar. 31, 2012
Consolidated Legg Mason
Deferred tax assets and valuation allowances relating to carryforwards
Deferred tax assets, U.S. federal net operating losses	$ 266,659		$ 219,984
Deferred tax assets, U.S. federal capital losses	74		74
Foreign tax credit carryforward	115,819		59,871
Deferred tax assets, charitable contributions	5,401		4,709
Deferred tax assets, U.S. state net operating losses	161,136	[1],[2]	151,762	[1],[2]
Deferred tax assets, U.S. state capital losses	34,960		39,046
Deferred tax assets, Non-U.S. net operating losses	22,011		26,704
Deferred tax assets, Non-U.S. capital losses	6,222		7,124
Total deferred tax assets for carryforwards	612,282		509,274
Valuation allowances, U.S. federal capital losses	74		74
Valuation allowances, U.S. federal foreign tax credits	23,608		6,542
Valuation allowances, U.S. charitable contributions	1,597		0
Valuation allowances, U.S. state net operating losses	25,951		23,911
Valuation allowances, U.S. state capital losses	34,960		39,046
Valuation allowances, Non-U.S. net operating losses	15,899		22,956
Valuation allowances, Non-U.S. capital losses	6,222		7,124
Valuation allowances for carryforwards	108,311		99,653
Non-U.S. other deferred assets	7,504		3,069
Total valuation allowances	$ 115,815		$ 102,722

[1] Substantially all of the U.S. state net operating losses carryforward through fiscal 2029.

[2] Due to potential for change in the factors relating to apportionment of income to various states, the Company's effective state tax rates are subject to fluctuation which will impact the value of the Company's deferred tax assets, including net operating losses, and could have a material impact on the future effective tax rate of the Company.