Percentage of assumed growth rate in projected cash flows, used as an input to measure fair value, average

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- Definition

Percentage of assumed growth rate in projected cash flows, used as an input to measure fair value, high end of range

+ References

No definition available.

+ Details

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- Definition

Percentage of assumed growth rate in projected cash flows, used as an input to measure fair value, low end of range

+ References

No definition available.

+ Details

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- Definition

Percentage of assumed royalties earned, used as an input to measure fair value.

+ References

No definition available.

+ Details

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- Definition

Amount used to represent the attrition when calculating the fair value of amortizable asset management contracts

+ References

No definition available.

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- Definition

Percentage of assumed long-term growth in AUM, used as an input to measure fair value.

+ References

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.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ 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

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- Definition

Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

+ References

No definition available.

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

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Intangible Assets and Goodwill Intangible Fair Value Assumptions (Details 2) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			$ 371,000
Assets Under Management [Member] \| RARE Infrastructure, Ltd [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Input, Projected Cash Flow Growth Rate, Average				7.00%
Fair Value Inputs, Discount Rate				6.50%
Asset Management Contracts \| RARE Infrastructure, Ltd [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Inputs, Long-term AUM Growth Rate		7.00%		7.00%
Fair Value Inputs, Attrition Rate		13.00%		8.00%
Fair Value Inputs, Discount Rate		15.50%		16.50%
Permal funds-of-hedge fund management contracts [Member] \| Permal [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Input, Projected Cash Flow Growth Rate, Low End of Range			(6.00%)
Fair Value Input, Projected Cash Flow Growth Rate, High End of Range			6.00%
Fair Value Input, Projected Cash Flow Growth Rate, Average			5.00%
Fair Value Inputs, Discount Rate			16.50%
Trade Names \| RARE Infrastructure, Ltd [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Input, Projected Cash Flow Growth Rate, High End of Range			10.00%
Fair Value Input, Projected Cash Flow Growth Rate, Average			7.00%
Fair Value Inputs, Discount Rate			16.50%
Trade Names \| Permal [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Input, Projected Cash Flow Growth Rate, Low End of Range		3.00%
Fair Value Input, Projected Cash Flow Growth Rate, High End of Range		9.00%
Fair Value Input, Projected Cash Flow Growth Rate, Average		7.00%
Fair Value Input, Royalty Rate		1.50%
Fair Value Inputs, Discount Rate		16.00%
Permal funds-of-hedge fund management contracts [Member] \| Permal [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount		4.00%
Consolidated Legg Mason, Inc.
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		$ 35,000	$ 371,000	$ 0
Permal [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Goodwill and Intangible Asset Impairment		17,000
RARE Infrastructure, Ltd [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Goodwill and Intangible Asset Impairment		$ 18,000
Trade Names \| Consolidated Legg Mason, Inc.
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			7,000
Permal funds-of-hedge fund management contracts [Member] \| Consolidated Legg Mason, Inc.
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			$ 364,000
Subsequent Event [Member] \| RARE Infrastructure, Ltd [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Goodwill and Intangible Asset Impairment	$ 34,000