Preston Medlin’s 22 points topped the Aggies (13-1, 4-0 Western Athletic). Kyisean Reed scored 17 points, Marcel Davis 14, Jarred Shaw 12 and Spencer Butterfield 11.
Shaw also had 12 rebounds to give Utah a 46-36 advantage on the glass.
Idaho (6-7, 2-1) had four men score in double figures. Connor Hill had 18, Stephen Madison had 14, Kyle Barone had 13 and Mike McChristian had 11.
Barone and McChristian each had 10 rebounds.
Utah State had a 17-6 scoring advantage off turnovers, but Idaho balanced that with a 17-6 scoring edge off the bench.
The score was tied 18 times and the lead changed hands 10 times.