I have not seen any Fleischmann's yeast sold in the supermarkets as "instant dry yeast". Their yeast for bread machines is instant dry yeast but is never called that to the best of my knowledge.
Most members use instant dry yeast (IDY) because it can be added directly to the flour and other dry ingredients without first rehydrating it. Active dry yeast (ADY) has to be first rehydrated in a small amount of water (about 4-5 times the weight of the ADY), at around 105 degrees F, for about 10 minutes. ADY is sensitive to water temperature, so it is important to measure the water temperature. Many people fail to do that and, as a result, can get degraded yeast performance. I have used both ADY and IDY for cold fermented pizza doughs but can't say that I detected any real differences in the final results.