Idaho Code § 3-404: Divisions of Idaho State Bar.

For the purposes of this act, the northern division of the Idaho State Bar will consist of Boundary, Bonner, Kootenai, Benewah, Shoshone, Latah, Nez Perce, Lewis, Clearwater and Idaho counties and all counties hereafter created therefrom. The western division shall consist of Payette, Gem, Washington, Canyon, Owyhee, Twin Falls, Jerome, Lincoln, Gooding, Camas, Blaine, Cassia, Adams and Minidoka counties, and all counties hereafter created therefrom. The central division shall consist of Ada, Boise, Elmore and Valley counties and all counties hereafter created therefrom. The eastern division shall consist of Lemhi, Custer, Butte, Clark, Fremont, Jefferson, Madison, Teton, Bonneville, Bingham, Bannock, Caribou, Power, Oneida, Franklin and Bear Lake counties, and all counties hereafter created therefrom.