What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT DIVERTED TO CLE. WITH THE APU INOPERATIVE, ENGINE 1 GENERATOT FAULT ECAM MESSAGE DISPLAYED AT CRUISE. FLIGHT CREW ACCOMPLISHED ECAM PROCEDURES TO RESET THE GENERATOR BUT IT DID NOT RESET SO THE FLIGHT CREW TURNED OFF THE GENERATOR FOR REMAINDER OF THE FLIGHT. THE AIRCRAFT LANDED SAFELY AT CLE AND TAXIED TO THE GATE UNDER ITS OWN POWER. MAINTENANCE REPLACED THE #1 ENGINE IDG AND ACCOMPLISHED A SATISFACTORY LEAK / OPERATIONAL CHECK.