Does one utterance of divorce count for my wife after I said to her father over the phone, "Your daughter is divorced," one time in a moment of anger?

Your statement to your wife's mother, "Indeed, your daughter is divorced," issues one divorce. If it was not the third divorce, then you may take her back as long as she is within her waiting period (iddah). It is advisable to avoid anger and to be deliberate during marital disputes, to seek wisdom in resolving them, to refrain from uttering words of divorce, and to solve problems between the spouses only, without involving others.