BOSTON (CBS/AP) – Beth Israel Deaconess Medical Center CEO Paul Levy is stepping down.

Levy announced his decision in a memo to staff Friday and posted it on his blog “Running a Hospital.”

“Likewise, for me personally, while it has been nine great years working with outstanding people, that is longer than I have spent in any one job, and I need some new challenges,” he wrote.

“So, last night, I informed the Chair of our Board that I will be stepping down as CEO. We will work out an appropriate transition period, and things will continue to run smoothly here. I leave confident that the Board will find many able candidates to succeed me.”

Levy came under fire last year when the hospital fined him $50,000 for having a personal relationship with a former female employee. He apologized.

The hospital asked Attorney General Martha Coakley to review their decision.

She called it “sufficient.” Coakley said top officials and board members were aware of the relationship as early at 2003 and damage to the hospital’s reputation could have been limited if action had been taken earlier.

Levy apologized again for his past mistakes in his farewell memo Friday.

“Over the last nine years, I have certainly made mistakes of degree, emphasis, and judgment. I have apologized to you directly for some of those, but I do so again, in the hope that such errors will not overshadow the many accomplishments and contributions of our hospital to the community and the health care industry. On the personal level, if I have slighted any one of you in any way or given you any cause for concern about my warm regard and respect for you, I doubly apologize.”

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