RELATED-PARTY TRANSACTIONS (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended	9 Months Ended			0 Months Ended		3 Months Ended	9 Months Ended			12 Months Ended			3 Months Ended	9 Months Ended
	Aug. 30, 2014 item	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Aug. 30, 2014 Manager item	Apr. 15, 2014 Manager	Sep. 30, 2014 Manager	Sep. 30, 2014 Manager	Sep. 30, 2014 Employees Unsecured promissory notes	Sep. 30, 2013 Employees Unsecured promissory notes	Dec. 31, 2013 Employees Unsecured promissory notes	Sep. 30, 2014 Australian JV	Dec. 31, 2013 Australian JV	Sep. 30, 2014 Moelis Asset Management LP	Sep. 30, 2014 Moelis Asset Management LP	Jun. 30, 2014 Moelis Asset Management LP
Related-party transactions
Aircraft lease term						10 years
Lease costs to be paid					$ 61		$ 156	$ 310
Expenses for use of the aircraft							221	301
Number of lessees of aircraft (other than the Company), including related party	2
Number of lessess of aircraft who are a related party	2				1
Unsecured promissory notes from employees									120		831
Fixed and variable interest rates (as a percent)									4.00%		4.75%
Principal repayments		831	383						831	383
Interest income recognized									5	29
Fee for services														500	960
Due to related party												425	1,145
Investment into the entity controlled by a related party		16,634		12,481												265
Revenue from Related Parties														$ 2,769	$ 3,717