Cy Garner, 40, was driving north on Idaho 51 near Riddle about 9 a.m. Thursday when his car went off the right shoulder on a curve and he overcorrected, Idaho State Police report.
The Honda Accord then went off the left shoulder and rolled, coming to rest on the left side of the highway, according to an ISP news release.
Garner, who was wearing a seat belt when he crashed, was taken to Saint Alphonsus Regional Medical Center in Boise by air ambulance. The highway was blocked for about three and a half hours.
The crash is under investigation by Idaho State Police.