PAE, long known for maintaining facilities overseas for the State Department, has significantly expanded its reach, adding business process outsourcing and national security work, among other areas, to become a $2.5 billion contractor. Now, John Heller, PAE's chief executive, has set his sights on further expansion, particularly with the company's ISR joint venture as well as into Energy Department facilities. PAE, which counts about 15,000 employees, was sold by Lockheed Martin to private-equity firm Lindsay Goldberg in 2011. According to...