Schwarzenegger: Affair Was 'Stupidest Thing' I Did

Arnold Schwarzenegger is revealing more about the affair that led to the split with his Maria Shriver, saying his actions were "stupid" and caused his wife "tremendous pain."

In his first interview since revealing last year that he had fathered a secret lovechild with his housekeeper, the former California governor opens up about his affair with Mildred Baena to CBS 60 Minutes correspondent Lesley Stahl. "I think it was the stupidest thing I've done in the whole relationship," he said. "It was terrible. I inflicted tremendous pain on Maria and unbelievable pain on the kids."

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Schwarzenegger also reveals intimate details of the affair and his relationship with Shriver in his new autobiography Total Recall: My Unbelievably True Life Story, which is due out on Monday. 

Shriver has not yet commented on the book, but Schwarzenegger told CBS that he doesn't think she'll be surprised by any of his revelations. "She knows that it's about my whole life and that I would not write a book and kind of leaves out that part and makes people feel like, 'Well, wait a minute. Are we just getting a book about his success stories and not talk about his failures?... I wanted to write a book about me.'"

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In the book, Schwarzenegger reportedly recounts that he had sex with housekeeper Mildred Baena in 1996 in the family guest house while his wife and the kids were away on vacation. The star says he tried for years to convince himself that Baena's husband was the father of the child, but eventually he had to face the truth when the boy grew up with obvious resemblance to him.

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Stahl's entire interview with Schwarzenegger can be seen on the season premiere of 60 Minutes this Sunday at 7 p.m. on CBS.