Bloomberg Opinion columnist Barry Ritholtz interviews Cal Turner Jr., who in 1965 began his career at the company founded by his father and grandfather in 1939: Dollar General. He succeeded his father as president in 1977 and as chairman in 1988. At the time of his retirement in 2003, Dollar General had grown into a New York Stock Exchange retailer with more than 6,000 stores in 27 states and annual sales in excess of $6 billion. He is the author of "My Father's Business: The Small-Town Values That Built Dollar General into a Billion-Dollar Company."