American Tower Corp. agreed to buy mobile-phone towers from Vodafone Group Plc 's Indian business and Idea Cellular Ltd., boosting its infrastructure in the country by a third, as the merging carriers sell off assets to raise cash for debt repayment amid a scathing price war. The Boston-based real estate investment trust agreed to pay 78.5 billion rupees ($1.2 billion) for about 20,000 towers owned by the carriers in a deal that is expected to be completed in the first half of 2018, American Tower said in a statement Monday. The assets will probably generate about $320 million in property revenue and $120 million in gross profits for their first full year under ATC, according to the statement.