Rough idle at stop light

I have a 95 Oldsmobile Cutlass Cierra. It has about 71,000 original miles on it. Yesterday was driving home and at one point stopped at a light and it started to idle rough. This morning got up and started the car it idled a little rough for a second then went to normal. I drove maybe a mile down the road and stopped at a light and it started to idle rough again. Wanted to maybe have some ideas of what it could be.
Thank you