The number of funds that Legg Mason consolidates as VIE's, by type of fund.

No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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Period Type:	instant

- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

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-Name Accounting Standards Codification
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Balance Type:	debit
Period Type:	instant

- Definition

Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

+ References

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- Definition

This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.

+ References

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

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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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Data Type:	na
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- Details

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- Details

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Variable Interest Entities and Consolidation of Investment Vehicles Information about Investments in CIV's (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018
Variable Interest Entity
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 16,297	$ 28,397			$ 44,608
Sponsored Investment Fund [Member]
Variable Interest Entity
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	0	1,690			11,224
Foreign Mutual Funds [Member]
Variable Interest Entity
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	15,806	19,303			25,966
Employee Owned Funds [Member]
Variable Interest Entity
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	0	5,188			4,544
Sponsored ETF [Member]
Variable Interest Entity
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 491	$ 2,216			$ 2,874
Consolidated Investment Vehicles [Member]
Variable Interest Entity
Number of Funds	6	10			13
Consolidated Investment Vehicles [Member] \| Sponsored Investment Fund [Member]
Variable Interest Entity
Number of Funds	0	2			2
Consolidated Investment Vehicles [Member] \| Foreign Mutual Funds [Member]
Variable Interest Entity
Number of Funds	5	5			7
Consolidated Investment Vehicles [Member] \| Employee Owned Funds [Member]
Variable Interest Entity
Number of Funds	0	1			1
Consolidated Investment Vehicles [Member] \| Sponsored ETF [Member]
Variable Interest Entity
Number of Funds	1	2			3
Voting Right Entities [Member]
Variable Interest Entity
Number of Funds	3	4		4
Consolidated Legg Mason, Inc.
Variable Interest Entity
Liabilities	$ 3,408,779	$ 3,470,025
Assets	7,917,437	$ 8,006,120
Future [Member]
Variable Interest Entity
Derivative, Notional Amount	1,505
Voting Right Entities [Member]
Variable Interest Entity
Number of Funds		5	4			7
Proprietary Funds [Member] \| Voting Right Entities [Member] \| Consolidated Legg Mason, Inc.
Variable Interest Entity
Investments	49,791	$ 41,774		$ 20,548
Collateralized Loan Obligations [Member]
Variable Interest Entity
Liabilities	563,300
Investments	5,000
Stockholders' Equity, Other	37,300
Assets	$ 563,600