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Represents the percentage of participation in future growth in value of the affiliate available for participation by key employees under the terms of a profits interest management equity plan.

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The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The total fair value of shares issued during the period under a deferred compensation arrangement.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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Amount of cash paid related to share-based compensation liabilities.

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- Definition

Percentage of vesting of share-based compensation awards.

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Stock-Based Compensation Management Equity Plans (Details 10) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2016
Consolidated Legg Mason, Inc.
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Stockholders' Equity Attributable to Noncontrolling Interest	$ 23,251	$ 0	$ 22,202
Management Equity Plan [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 19,499	1,301
Management Equity Plan [Member] \| Clarion Partners [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Profits interests equity plan participation percentage	15.00%
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 15,200
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	20.00%
Deferred Compensation Arrangement with Individual, Fair Value of Shares Issued	$ 18,700
Management Equity Plan [Member] \| Royce [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Profits interests equity plan participation percentage	16.90%
Management Equity Plan [Member] \| Permal [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Profits interests equity plan participation percentage	15.00%
Aggregate Cost of Awards	$ 9,000
Deferred Compensation Arrangement with Individual, Compensation Expense	3,481	454
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Share-based Liabilities Paid	$ 7,150
Management Equity Plan [Member] \| ClearBridge Investments [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Profits interests equity plan participation percentage	15.00%
Aggregate Cost of Awards	$ 16,000
Deferred Compensation Arrangement with Individual, Compensation Expense	818	$ 847
Deferred Compensation Arrangement with Individual, Fair Value of Shares Issued	$ 22,160