at leisure
1. When one has the time to do something. In this usage, a possessive pronoun is used between "at" and "leisure." No rush, you can fill out that paperwork at your leisure
2. In a relaxed manner. I like to spend my weekends reading at leisure.
3. With free time; unoccupied. I just graduated from college—can't I spend some time at leisure?
at one's leisure
Whenever one wishes, at one's convenience, as in At your leisure, please look over this manuscript and give me your comments. [1400s] Also see at leisure.