The pilot reported that during the landing at the destination airport, the airplane floated down the runway, landed long, and did not slow as expected. He continued to apply the brakes as the airplane neared the end of the runway, then felt a gust of wind from the left. The pilot was unable to maintain control and the airplane veered off the right side of the runway. The airplane nosed over in the grass and came to rest inverted which resulted in substantial damage to the right wing and empennage. The pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation and that to prevent the accident he could have landed closer to the threshold of the runway. The responding FAA inspector examined the airplane and found that the throttle was not all the way to idle.