Idaho Code § 34-1202
The counting must commence by comparison of the ballots and the poll lists from the commencement, and a correction of any mistake that may be found therein, until they are found to agree. The ballot box shall be opened and the ballots found therein counted by the judges, unopened and the number of ballots in the box must agree with the number marked in the poll book as having received a ballot, and this number, together with the number of spoiled ballots, must agree with the number of stubs or counterfoils in the books from which the ballots have been taken. If the number of ballots issued does not agree with the number of stubs or counterfoils, the election judges shall have authority to make any decision to correct the situation; but this shall not be construed to allow the judges to void all ballots cast at that polling place.
When duplicate ballot boxes are used in a precinct, the duties herein prescribed shall be done after all of the votes have been tallied.
Idaho Code § 34-1202