Unfortunately, the details stopped there. Aside from alcohol being involved, there was nothing else. It is assumed that it must be serious for his contract to be terminated, but at the same time, if Gary Bettman allowed him to come back, it must not be so major.
However, in the eyes of the NHL, it's behavior that can happen, and it may even happen quite regularly. Perry made a mistake one night in Columbus, had too much to drink, and made advances towards a staff member working at NBC.
This doesn't excuse the action, but it helps us understand why all of this has become such a big deal. With any other team, it might not have had such consequences.