how to get last id when a row was insert in laravel eloquent in Model

I've used setNotification method of model by initial data from Controller within a variable $data as array. I have used self:: in this method instead of used table or Notification::save() or $obj->save(). by this way I don't know how to get Id which the last id after insert was done in laravel because I used $this->attributes that it is the protected variable in Model.

class Notification extends Model
{

    protected $table = 'notification';
    public $timestamps = true;
    private $_data = false;


    public function setNotification($data)
    {
        if (is_array($data)) {
            $this->attributes = $data;
            self::save();
        }
    }
}

via Chebli Mohamed