NEW YORK — Susan Lyne, who rebuilt the Martha Stewart Living business in the aftermath of the namesake founder's legal woes, has stepped down as chief executive, and the job is being split between two company executives.

The management changes come as Martha Stewart Living Omnimedia Inc. navigates through a tough advertising climate and confronts a consumer, saddled with high gas and food prices, who may no longer be eager to replicate the home diva's lifestyle with all things Martha Stewart.

Lyne "did a great job dealing with the issues that arose in the wake of Martha Stewart's legal troubles," said David Bank an analyst at RBC Capital Markets. But he expressed concern that a challenging environment has stalled the company's growth and could dampen stores' willingness to sign up for big-scale deals like the one recently forged with Macy's Inc. and Costco Wholesale Corp.

The New York-based media empire said that Wenda Harris Millard, 53, who is currently president of media at Martha Stewart, and Robin Marino, 53, president of merchandising, would be co-CEOs.

The company also announced in a regulatory filing yesterday that it will form an advisory committee, called the office of the chairman, to focus on the strategic direction of the company. The committee will be comprised of the two new co-CEOs, Chairman Charles Koppelman, Chief Creative Officer Gael Towey and the company's founder, Martha Stewart.