Regulatory Requirements - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Regulatory Requirements
Minimum net capital requirement	$ 250
Moelis US
Regulatory Requirements
Net capital	92,669	$ 29,259
Net capital in excess of required net capital	92,419	29,009
Moelis UK
Regulatory Requirements
Net capital	56,157	50,498
Net capital in excess of required net capital	$ 56,098	$ 50,439

Regulatory requirements

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- Definition

The amount of net capital in excess of the alternative minimum required net capital.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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- Definition

Amount of net capital requirement computed under the alternative method allowed under regulatory reporting requirements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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- Definition

Net capital is equal to the net worth of the broker dealer, less certain items such as exchange memberships, carrying value of securities not readily marketable, haircuts on marketable securities in proprietary accounts, furniture and equipment and other illiquid assets as defined.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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