Eight healthcare providers on Long Island were among 20 in New York that overbilled the state millions of dollars in this decade, the state comptroller's office has said. A 2007 audit conducted by the comptroller's office found that the providers submitted $10 million in inflated claims, mostly by waiving patients' out-of-network fees for the Empire Plan, the state's largest employee health plan. Four of them have paid nearly $7 million in restitution plus civil fines.