Acquisitions Clarion Partners Fair Value Inputs (Details) - Clarion Partners [Member]	3 Months Ended
Jun. 30, 2016
Business Acquisition [Line Items]
Fair Value Inputs, Long-term EBITDA Growth Rate	6.00%
Fair Value Assumptions, Risk Free Interest Rate	2.30%
Legg Mason, Inc
Business Acquisition [Line Items]
Fair Value Assumptions, Expected Volatility Rate	38.00%
Clarion Partners [Member]
Business Acquisition [Line Items]
Fair Value Assumptions, Expected Volatility Rate	30.00%

In order to calculate the present value of the performance units issued to Clarion the long-term growth rate of their EBITDA was used.

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

+ Details

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- Details

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- Details

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- Details

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