Peter Oppenheimer, senior vice president and chief financial officer of Apple, will retire from the company at the end of September, after spending 18 years with the Mac maker, it was announced on Tuesday.

Upon Oppenheimer's departure, Luca Maestri, Apple's current vice president of Finance and corporate controller, will serve as the company's new CFO. A transition between the two employees will begin in June.

"Peter has served as our CFO for the past decade as Apple's annual revenue grew from $8 billion to $171 billion and our global footprint expanded dramatically," said Apple Chief Executive Tim Cook. "His guidance, leadership and expertise have been instrumental to Apple's success, not only as our CFO but also in many areas beyond finance, as he frequently took on additional activities to assist across the company. His contributions and integrity as our CFO create a new benchmark for public company CFOs.

Outgoing Apple CFO Peter Oppenheimer said he plans to spend more time with his family, travel, and finish the requirements for a pilot's license. "Peter is also a dear friend I always knew I could count on. Although I am sad to see him leave, I am happy he is taking time for himself and his family. As all of us who know him would have expected, he has created a professional succession plan to ensure Apple doesn't miss a beat."

Oppenheimer's retirement comes as the outgoing CFO was announced on Monday to be joining the board of directors at Goldman Sachs. He has spent the last decade as Apple's chief financial officer, and has been with the company since 1996.

"I love Apple and the people I have had the privilege to work with and after 18 years here, it is time for me to take time for myself and my family," Oppenheimer said in a statement. "For quite some time, I have wanted to live on the central coast of California and get more involved at Cal Poly, my alma mater; spend more time with my wife and sons; travel to interesting parts of the world; and something I have wanted to do for years— finish the requirements for my pilot's license."

During Oppenheimer's tenure, Apple has seen its annual revenue grow more than twentyfold. The company credits him with overseeing development of "a disciplined global financial strategy, robust systems and procedures, and a very strong balance sheet."

Oppenheimer is a graduate of California Polytechnic and he has an MBA from the University of Santa Clara. In addition to Goldman Sachs, Oppenheimer also serves on the boards of the California Polytechnic State University Foundation, as well as Sacred Heart Schools in Atherton, Calif.

His replacement, Maestri, has over 25 years of experience in building and leading finance teams in global companies, Apple said. He previously served as CFO of Xerox before joining Apple in early 2013. Apple's next CFO, Luca Maestri, has been with the company since early 2013. He previously served as CFO at Xerox, Nokia Siemens Networks, and General Motors.

Prior to Xerox, Maestri worked for 4 years at Nokia Siemens Networks, and 20 years at General Motors, where he handled financial operations for the company in a variety of roles across the globe. Maestri received a bachelor's degree in economics from Luiss University in Rome in 1988, and a master's degree of science from Boston University in 1991. He is also a board member of The Principal Financial Group.

"Luca has over 25 years of global experience in senior financial management, including roles as a public company CFO, and I am confident he will be a great CFO at Apple," Cook said. "When we were recruiting for a corporate controller, we met Luca and knew he would become Peter's successor. His contributions to Apple have already been significant in his time with us and he has quickly gained respect from his colleagues throughout the company."