I've flown into DTW several times and I know the terminal is fairly easy to get around in, but I've never cleared customs there and I'm not sure if 1:20 will be sufficient. I'll be arriving on DL 276 from NRT in row 35, which is kind of close to the front but not really. I'm assuming my connecting flight will be in Concourse A. I don't plan to check any bags. But I'm wondering if there's some labyrinth-like maze I'll need to go through in order to reach customs, and how long I can expect the lines to be.

If any of you have done this, is 1:20 a reasonable enough time to get off the plane, clear customs and make it to the gate for my next flight?