John Pew, 64, died at Saint Alphonsus Regional Medical Center in Boise, where he was taken after the crash.
Pew was headed north on Northside Boulevard early Tuesday when a car westbound on Interstate 84 went off the overpass crossing Northside and hit his pickup truck.
Idaho State Police arrived on scene at 5:17 a.m. They say Tyler Callahan, 21, of Weiser, was the driver of the Chevrolet Impala that went off the freeway’s left shoulder and onto Northside Boulevard. It was not immediately clear why Callahan veered off the interstate.
Callahan and two juvenile passengers in his Impala were also taken by ambulance to Saint Alphonsus. Callahan was listed early Tuesday afternoon in serious condition. Conditions on the two passengers were unavailable because their names were not released by police.
Northside Boulevard was closed for nearly three hours as emergency crews worked at the scene.
The crash remains under investigation.