Minnetonka-based UnitedHealth Group Inc., the nation's largest insurer, announced a management restructuring Wednesday that includes the departure of a high-profile executive.

The managed care giant said Executive Vice President Gail Boudreaux, 54, will leave effective Feb. 27. Other changes include the promotions of three other executives and the creation of a five-member "Office of the Chief Executive" that will manage the company over the next five years.

Boudreaux, who has been with the company since 2008 and heads UnitedHealth's insurance division, is due a severance of up to $23 million as part of the change, according to securities filings and company statements.

"We believe UnitedHealth was due for a management shake-up given recent performance, which lagged its peers in certain areas … many of which were Boudreaux's responsibilities," Peter Costa, a senior stock analyst at Wells Fargo, wrote in a note to investors Wednesday. The changes "will likely leave investors a bit unsettled, but perhaps not disappointed."

As part of the management shuffle, current Chief Financial Officer David Wichmann, 52, was named president of UnitedHealth Group and will assume oversight responsibility for the insurance division, UnitedHealthcare.

Wichmann will move out of his role as company CFO over the next year as he settles into the job of president. Costa's note speculated that the expanded job title may set up Wichmann as successor to UnitedHealth Group's CEO, Stephen Hemsley.

Larry Renfro, 60, will remain CEO of UnitedHealth's fastest-growing division, data-analytics powerhouse Optum, while he assumes the vice chairman title and new oversight for companywide "strategic relationships, key client relationships, and … business growth efforts."

Also serving in the five-member Office of Chief Executive are: Hemsley, Chief Legal Officer Marianne Short, and Ellen Wilson, executive vice president for human capital. None of their jobs are changing in the move.

Dirk McMahon, the current chief operating officer at Optum, becomes executive vice president for enterprise operations at UnitedHealth Group, and will report to Wichmann.

"We are bringing forward the next generation of leaders to work together, over the next five years, to continue diversifying our offerings, advancing our industry-leading technology and data services … and innovating around consumers and next-stage care provision," Hemsley said in a public statement.

Company officials said Boudreaux had achieved the growth and performance goals that were announced when she joined UnitedHealth six years ago. But she didn't achieve every goal set out for her division in recent years, which meant she didn't receive the highest possible incentive payments for performance.

Although the company was happy with the strong performance in commercial benefits and state-contract business, UnitedHealthcare initially struggled to meet the demands of its new contract to manage military health care benefits under the Tricare program and saw lower-than-expected performance in a federal ratings system that judges how well companies manage private Medicare plans.

As a result, she had 15 percent knocked off her $1.3 million performance bonus for fiscal 2013, and she will not receive a payout for a long-term incentive program based on performance in 2012-14, securities filings and public statements say.

Over the next two years she will receive severance payments that are spelled out in her employment agreement, the latest version of which says she's entitled to as much as $6 million in cash payments and $17 million in accelerated equity payments if she's terminated without cause.

Boudreaux signed a two-year noncompete agreement as part of her separation package.

UnitedHealth Group stock closed at $95.68 Wednesday, down 1 cent.

Christopher Snowbeck • 612-673-4744

Twitter: @chrissnowbeck