PAE, the company divested by Lockheed in 2011, is bulking up, announcing Friday that it has bought the 1,900-employee global security and solutions business of U.S. Investigations Services. The deal comes as many contractors are seeking to diversify their businesses. John Heller, PAE's chief executive, told InsideDefense.com that the acquisition would expand PAE's customers and skills, particularly expanding its work with the Department of Homeland Security and the Justice Department. The terms of the acquisition were not disclosed. Since...