Susan owns a Van Gogh painting valued at $10 million. In addition to the painting, Susan owns approximately $15 million of other assets. For estate planning purposes, Susan has given the painting to the Van Gogh museum in Amsterdam with the understanding that Susan will retain the painting in her residence during her lifetime; the museum to get the painting after her death. In 2006, the value of Susan's retained interest in the painting is $2 million. If Susan dies in 2006, what is the value of Susan's gross estate?