Can minor detail be too much?

Yes and no. Overall, yes. Its great to add flavor or details to your tavern, inn or even town. Careful though, as sometimes your minor detail will draw the attention of players to investigate something that has nothing to do with the game at hand. For example in the Book of Sorrows campaign Podcast I put up for AD&D 1E fans of the RFI Podcast, my players came into a mysterious town, and when inside the tavern, I described the eating/bar area, and happened to describe one man in too much detail, but saying he was taller, slouched over and his face was hidden. While this man had nothing to do with what was going on, my players kept watching him and asking more and more about him, until they finally had to talk to him. Who's fault is this? Mine of course, I messed up, but as a great on the fly DM that I am, I quickly worked up a purpose to him being there and I kept adding more detail to him, by saying that once in a while they noticed his gloves were off and you saw a green scaly hand. Luckily my players did not bother much with him other then try talking to him, and walked away. But here is a lesson for all you DM's out there, be careful!