Local doctors have padded their incomes with thousands of dollars from pharmaceutical drug makers, part of a multibillion-dollar industry effort lining the pockets of doctors across California and the United States . The payments are a fraction of the 2 million documented transactions between medical professionals and 15 of the world's largest drug manufacturers compiled by the investigative journalism nonprofit ProPublica. They detail an eye-popping $2 billion in long-secret payments for meals, travel expenses and speaking fees that experts say represents a small fraction of drug makers' financial dealings with doctors.