I just had a phone interview with Moelis... nervous but wondering if anyone knows how long they take to get back to you?
It varies and no one will ever know. Simply just acknowledge that you did your best in the phone interview and even if you didn't, there's nothing you can do to change the outcome right now. If you don't hear anything within a week, I would send a brief email asking about your candidacy.
They could call you 30 minutes after your phone interview, or even up to a week later indicating that they would like to move forward with you. It all depends on how Moelis is running their process and how busy the person running the recruiting process is.