Significant Accounting Policies (Details 1) (Legg Mason, Inc., USD $) In Thousands, unless otherwise specified	3 Months Ended
Jun. 30, 2013	Jun. 30, 2012
Legg Mason, Inc.
Net income (loss) attributable to noncontrolling interests
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	$ 882	$ (661)
Net income (loss) reclassified to appropriated retained earnings for consolidated investment vehicle	398	(2,865)
Total	$ 1,280	$ (3,526)

Amount of Net Income (Loss) attributable to noncontrolling interest.

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-Name Accounting Research Bulletin (ARB)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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