Idaho Code § 39-1320
The organization of a hospital district shall be initiated by a petition filed with the board of county commissioners of the county of [in] which the said district is situated. Said petition shall be signed by not less than ten per cent (10%) of the qualified electors and taxpayers of the proposed district. The equalized county assessment list last preceding the presentation of the petition for the organization of the hospital district shall be sufficient evidence of the title for the purpose of this act, but other evidence may be received.
The petition shall set forth:
Similar petitions or duplicate copies of the same petition for the organization of the same district may be filed and shall together be regarded as one (1) petition. All petitions filed prior to the hearing on the first petition filed shall be considered by the board the same as though filed with the first petition placed on file.
Provided, however, that no such district shall be organized unless it shall appear that the boundaries of said district are wholly within the limits of a single county and that there shall be no unnatural extension of the boundaries of said district.
The petition together with all maps and other papers filed therewith shall at all proper hours be open to public inspection in the office of the clerk of the board of county commissioners between the date of their said filing and the date of an election to be held as hereinafter provided.
Idaho Code § 39-1320