I really don't think Thomas Edison stole ideas from Tesla. Tesla and Edison were both great inventors during their time. According to history, Edison owned a company in France, Société Electrique Edison, where Tesla was working as an employee of Edison.
Tesla was able to gather a lot of knowledge about practical engineering and this helped him to know how AC motors truly work. However, due to his outstanding performance, Tesla caught the attention of one of the engineers at Edison's company in France, and he was transferred to work at another company of Edison in the United States.
During his six months stay in this company, he worked for the Edison Construction Department and was able to develop an arc lighting system. But due to some reasons, Edison decided not to use it. As a result, Tesla left the company and patterned with another company to sell the invention. Edison didn't steal Tesla's ideas because the arc lighting system was developed when Tesla was an employee of Edison.