Related-Party Transactions	12 Months Ended
Dec. 31, 2018
Related Party Transactions [Abstract]
Related-Party Transactions	11. RELATED‑PARTY TRANSACTIONS Aircraft Lease—On August 30, 2014, a related party, Moelis & Company Manager LLC ("Manager"), acquired an aircraft with funds received solely from its managing member (Mr. Moelis). The aircraft is used and operated by the Company pursuant to a dry lease with Manager which terminates on December 31, 2019. The terms of the dry lease are comparable to the market rates of leasing from an independent third party. Pursuant to this dry lease arrangement, the lessee is obligated to bear its share of the costs of operating the aircraft. For the years ended December 31, 2018, 2017, and 2016, the Company incurred $1,872, $1,872 and $1,248 in aircraft lease costs to be paid to Manager, respectively. In addition, Mr. Moelis is the other lessee of the aircraft and shares the operating and related costs of the plane in proportion to his respective use pursuant to a cost sharing and operating agreement. Promissory Notes—As of December 31, 2018, there were $189 of unsecured promissory notes from employees held by the Company (December 31, 2017: $552). Any outstanding balances are reflected in other receivables on the consolidated statements of financial condition. The notes held as of December 31, 2018 and 2017 bear a fixed interest rate of 4.00%. During the years ended December 31, 2018, 2017 and 2016, the Company received $366, $781 and $0, respectively, of principal repayments and recognized interest income of $13, $27 and $25, respectively, on such notes, which is included in other income and expenses on the consolidated statements of operations. Services Agreement—In connection with the Company’s IPO, the Company entered into a services agreement with a related party, Moelis Asset Management LP, whereby the Company provides certain administrative services, technology, and office space to Moelis Asset Management LP for a fee. This fee totaled $537, $1,118 and $1,283 for the years ended December 31, 2018, 2017 and 2016, respectively. The amount of the fee is based upon the estimated usage and related expense of all shared services between the Company and Moelis Asset Management LP during the relevant period, and will be assessed periodically by Management as per the terms of the agreement. As of December 31, 2018 and 2017, there were no balances due from Moelis Asset Management LP. Moelis Australia—As of December 31, 2018 and 2017, the Company had a net balance due to Moelis Australia of $1,673 and $128 due from Moelis Australia, respectively, which are reflected in accrued and other receivables on the consolidated statements of financial condition. These balances consist of amounts due to or from Moelis Australia for advisory services performed as well as billable expenses incurred by the Company on behalf of Moelis Australia during the period. The relationship between the Company and Moelis Australia is governed by a services agreement. Revenues—From time to time, the Company enters into advisory transactions with Moelis Asset Management LP and its affiliates. The Company earned revenues associated with such transactions of $1,882, $1,240 and $7,281 for the years ended December 31, 2018, 2017 and 2016, respectively. As of December 31, 2018, and 2017, the Company had balances due from Moelis Asset Management LP and its affiliates related to such revenues of $1,628 and $0, respectively.

Related-Party Transactions

12 Months Ended

Dec. 31, 2018

11. RELATED‑PARTY TRANSACTIONS

Aircraft Lease—On August 30, 2014, a related party, Moelis & Company Manager LLC ("Manager"), acquired an aircraft with funds received solely from its managing member (Mr. Moelis). The aircraft is used and operated by the Company pursuant to a dry lease with Manager which terminates on December 31, 2019. The terms of the dry lease are comparable to the market rates of leasing from an independent third party. Pursuant to this dry lease arrangement, the lessee is obligated to bear its share of the costs of operating the aircraft. For the years ended December 31, 2018, 2017, and 2016, the Company incurred $1,872, $1,872 and $1,248 in aircraft lease costs to be paid to Manager, respectively. In addition, Mr. Moelis is the other lessee of the aircraft and shares the operating and related costs of the plane in proportion to his respective use pursuant to a cost sharing and operating agreement.

Promissory Notes—As of December 31, 2018, there were $189 of unsecured promissory notes from employees held by the Company (December 31, 2017: $552). Any outstanding balances are reflected in other receivables on the consolidated statements of financial condition. The notes held as of December 31, 2018 and 2017 bear a fixed interest rate of 4.00%. During the years ended December 31, 2018, 2017 and 2016, the Company received $366, $781 and $0, respectively, of principal repayments and recognized interest income of $13, $27 and $25, respectively, on such notes, which is included in other income and expenses on the consolidated statements of operations.

Services Agreement—In connection with the Company’s IPO, the Company entered into a services agreement with a related party, Moelis Asset Management LP, whereby the Company provides certain administrative services, technology, and office space to Moelis Asset Management LP for a fee. This fee totaled $537, $1,118 and $1,283 for the years ended December 31, 2018, 2017 and 2016, respectively. The amount of the fee is based upon the estimated usage and related expense of all shared services between the Company and Moelis Asset Management LP during the relevant period, and will be assessed periodically by Management as per the terms of the agreement. As of December 31, 2018 and 2017, there were no balances due from Moelis Asset Management LP.

Moelis Australia—As of December 31, 2018 and 2017, the Company had a net balance due to Moelis Australia of $1,673 and $128 due from Moelis Australia, respectively, which are reflected in accrued and other receivables on the consolidated statements of financial condition. These balances consist of amounts due to or from Moelis Australia for advisory services performed as well as billable expenses incurred by the Company on behalf of Moelis Australia during the period. The relationship between the Company and Moelis Australia is governed by a services agreement.

Revenues—From time to time, the Company enters into advisory transactions with Moelis Asset Management LP and its affiliates. The Company earned revenues associated with such transactions of $1,882, $1,240 and $7,281 for the years ended December 31, 2018, 2017 and 2016, respectively. As of December 31, 2018, and 2017, the Company had balances due from Moelis Asset Management LP and its affiliates related to such revenues of $1,628 and $0, respectively.