protected function getHours()
    {
        $intSecondsPerHour = ($this->isPositive()) ? DateTimeSpan::SECONDS_PER_HOUR : ((-1) * DateTimeSpan::SECONDS_PER_HOUR);
        $intHours = floor($this->intSeconds / $intSecondsPerHour);
        if ($this->isNegative()) {
            $intHours = (-1) * $intHours;
        }
        return $intHours;
    }