Idaho Code § 59-904A
In the event of a vacancy in the house of representatives or senate of the state of Idaho, such vacancy shall be filled as herein provided. The legislative district committee of the same political party, if any, of the former member whose seat is vacant shall submit, within fifteen (15) days, a list of three (3) nominations to the governor. The governor shall fill the vacancy by appointment from the list of three (3) nominations within fifteen (15) days. If no appointment has been made within fifteen (15) days, the legislative district committee shall designate one (1) of the three (3) nominees to fill the vacancy. The vacancy shall be so filled until the next general election after such vacancy occurs, when such vacancy shall be filled by election.
The legislative district committee of the same political party, if any, of the former member, shall select a person who possesses the constitutional qualifications to fill the vacant office to which he is nominated, and who is affiliated with the same political party, if any, as the former member whose seat is vacant. Upon the failure of the committee to make such selection before the expiration of the fifteen (15) day period the governor shall within five (5) days, fill said vacancy by appointing a person having the qualifications above set forth.
Idaho Code § 59-904A