Just chiming in that I've got a 2016 with about 18k miles that has terrible idle. I'm headed into the shop anyway, so I will have them look at it; but when at a stand still, either at startup or a stop light, I get dips and surges that almost feel like it will stall but it never does. Kind of strange with so few miles. It has been doing this for the past 1.5k miles. While in motion, all is smooth as silk.
Could be a bad sensor sending bad data... http://www.autoserviceprofessional.com/article/92420/The-dreaded-engine-surge?Page=5