HOUSTON--(BUSINESS WIRE)--Insperity, Inc. (NYSE: NSP), a leading provider of human resources and business performance solutions for America’s best businesses, today announced that it has extended its arrangement for medical and dental coverage through 2019 with UnitedHealthcare, a UnitedHealth Group company (NYSE:UNH). This arrangement reflects the dedication of both companies to offer the best health care and health care reform solutions in the marketplace. “We are extremely pleased to deepen