BizProcDocument::getStorageIdByType

static function getStorageIdByType($documentType)
{
	$items = explode('_', $documentType);
	if(count($items) != 2)
	{
		return null;
	}
	$storageId = (int)$items[1];
	if($storageId <= 0)
	{
		return null;
	}
	return $storageId;
}