A former partner at the scandal-ridden stock-trading firm that inspired the blockbuster movie "The Wolf of Wall Street" is speaking out as a new documentary about the firm premieres on Paramount+.

"My lifestyle was insane," Howie Gelfand, who rose to become a partner at Stratton Oakmont, said in an interview on "CBS Mornings."

The three-part docuseries "The Real Wolf of Wall Street" gives an inside look at the firm run by Jordan Belfort, who was portrayed by Leonardo DiCaprio in the feature film. 

Gelfand joined Stratton Oakmont when he was 19. He told "CBS Mornings" that within a year of starting he was making over $100,000 a month — far more than the $35,000 a year that he had been earning.

Eventually, he was making over $1.5 million a year. When he found out that what the firm was doing was illegal, he thought it was just business as usual for Wall Street.

But Gelfand learned that his fast-paced lifestyle came with a cost.

"I was the most miserable millionaire — 325 pounds, drugs, booze," Gelfand said. "I couldn't figure enough ways to subconsciously kill myself because what I was doing was horrible, so I had to anesthetize myself every day to do what I was doing."

The docuseries includes new revelations from over 15,000 internal FBI and government documents obtained by investigative reporter and executive producer Jason Leopold using the Freedom of Information Act. 

"The Real Wolf of Wall Street" is streaming now on Paramount+, a division of Paramount, the parent company of CBS News.