Unless otherwise provided by law, any final decision or order adverse to a party in a contested case shall be in writing or stated in the record. Any final decision shall include findings of fact and conclusions of law, separately stated. Findings of fact, if set forth in statutory language, shall be accompanied by a concise and explicit statement of the underlying facts supporting the findings. Unless otherwise provided by law, parties shall be notified either personally or by mail to their last known address of any decision or order. Upon request a copy of the decision or order shall be delivered or mailed forthwith to each party and to his attorney of record.