Idaho Code § 57-401
Whenever the holder of any coupon bond, already issued or hereafter issued by the state of Idaho, or by any county, city, town, township, board of education, school district or other subdivision, now or hereafter existing in this state, shall present any such bond to the treasurer or other officer of the state or of such corporation, or subdivision, who by law performs the duties of treasurer, with a request for the registration of such bond as to principal only, in the name of such holder, it shall be the duty of such treasurer or such other official, to register such bond in the name of such holder, as to principal only, on the treasurer's books, which registration shall be similarly noted on the bond. After registration as to principal only, such bond may be discharged from registration by being transferred to bearer, after which it shall be transferable by delivery, but it may be again registered as before.
Idaho Code § 57-401