Traditional pensions are disappearing in America, and the federal government just made it easier for employers to get rid of them. With no fanfare in early March, the Treasury Department issued a notice that allows employers to buy out current retirees from their pensions with a one-time lump sum payment. The decision reverses Obama-era guidance, issued in 2015, that had effectively banned the practice after officials determined that lump-sum payments often shortchanged seniors.