Luminant, the Dallas-based electricity generator that has protested federal regulators' timetable to curtail emissions from its coal-fired plants, said Monday it will idle two of those facilities and stop mining Texas lignite at some locations by the end of the year, costing about 500 jobs. Luminant said it took the actions to prepare to meet the Environmental Protection Agency's Cross-State Air Pollution Rule, which requires electricity generators in 27 states to cut emissions by Jan. 1, a deadline CEO David Campbell called "unrealistic." The company said it will spend about $280 million through 2012 on emissions control equipment, but won't...