protected function getDays()
    {
        $intSecondsPerDay = ($this->isPositive()) ? DateTimeSpan::SECONDS_PER_DAY : ((-1) * DateTimeSpan::SECONDS_PER_DAY);
        $intDays = floor($this->intSeconds / $intSecondsPerDay);
        if ($this->isNegative()) {
            $intDays = (-1) * $intDays;
        }
        return $intDays;
    }