Represents the cumulative dollar amount of dividends declared by a subsidiary or equity method investee.

No definition available.

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- Definition

Represents payments made to terminate revenue sharing agreements.

+ References

No definition available.

+ Details

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Namespace Prefix:	mc_
Data Type:	xbrli:monetaryItemType
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- Definition

The percentage of equity of the subsidiary or equity method investee issued or sold per stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	mc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

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- Definition

The profit or loss on sales of previously unissued stock by subsidiaries or equity investees made to investors outside the consolidated group that is not reported as operating income. Represents the difference in the parent company's carrying amount of the equity interest in the subsidiary or equity investee immediately before and after the transaction.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

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- Definition

Cash dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporations that are returns of capital. Excludes dividends or distributions from equity method investments classified as operating activities.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=mc_MoelisAustraliaHoldingsPTYLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_IPOMember
Namespace Prefix:
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SUBSEQUENT EVENTS (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions					3 Months Ended
	Apr. 21, 2017	Apr. 18, 2017	Apr. 10, 2017	Mar. 20, 2017	Jun. 30, 2017	Mar. 31, 2016
Subsequent events
Dividends received accounted for as a return on investment						$ 9
Subsequent event
Subsequent events
Dividends declared per share	$ 0.37
Moelis Australia Holdings
Subsequent events
Dividends declared				$ 23,300
Moelis Australia Holdings \| Subsequent event
Subsequent events
Dividends received accounted for as a return on investment		$ 11,700
IPO \| Moelis Australia Holdings \| Subsequent event
Subsequent events
Shares issued			25
Percentage of equity included in offering			20.00%
Proceeds from issuance of shares			$ 44,100
Gain recognized by Company on offering					$ 15,200
Ownership interest before offering (as a percent)			50.00%
Ownership interest after offering (as a percent)			40.00%
Payment to terminate asset management related revenue sharing agreement			$ 9,600