If you are flying on American Airlines they require you be there 3 hours prior to departure
AA requires that you check in 3 hours before your flight. You can do that online. If you are checking bags you need to be there 90 minutes before the flight. If you are not checking bags and check in online there is no mandate other than allowing enough time to clear customs and security.
The situation at STT now is not typical. With only a few flights operating each day the time to check in and clear through is less than 30 minutes.
