An oil painting by Paul Cézanne was sold privately in 2013 for $100 million by the Edsel & Eleanor Ford House, a nonprofit cultural institution, in Grosse Ponite Shores, Michigan. The sale to a private buyer was kept quiet so as to not influenec negotiations in keeping the Detroi Institute of Arts collections intact, reported the Detroit Free Press on Friday.

An unsolicited offer for the painting in mid-2013 was reportedly turned down by the historic house's board. The buyer then came back with an offer of $100 million that was accepted, possibly placing the landscape among the 15 most expensive works of art ever sold.

"La Montagne Sainte-Victoire vue du bosquet du Château Noir," painted around 1904, was in the Ford family collection since the mid-20th century.  Ford House president Kathleen Mullins.

The house's seven-member board — comprised of six Ford family members and the family's lawyer — turned down an offer for a Cezanne watercolor also in the collection. Other artwork, such as works by Henri Matisse and Diego Rivera, will not be sold.

"This was really a once-in-a-lifetime offer," said Ford House president Kathleen Mullins. "The family thought it was a way to guarantee the estate would be taken care of the way Eleanor would have wanted."

The sale appeared in the 2013 tax form of the Ford House, which is on solid financial footing and carries no debt. Proceeds from the sale will go to a special endowment for preservation, conservation and restoration of the collection, including the 1929 English Cotswold-style mansion designed by architect Albert Kahn, the landscape and gardens created by Jens Jensen and furnishings and objects inside the house.

A separate operating endowment of $86 million is already in place at the Ford House, which draws 60,000 visitors per year.