function Expander_Hide(elementId, parentId) {
	var element = Bd_GetElement(elementId);
	element.style.visibility = "hidden";
	element.style.display = "none";
}

function Expander_Switch(elementId, parentId, subId) {

	var element = Bd_GetElement(elementId);
	var parent = Bd_GetElement(parentId);
	var sub = Bd_GetElement(subId);
			
	if (element.style.visibility == "visible") 
	{
		parent.className = "Expander_Item_Visited";
		
		if(sub != null)
			sub.className = "Expander_Item_Sub_Visited";
		element.style.visibility = "hidden";
		element.style.display = "none";
	}
	else 
	{
		parent.className = "Expander_Item_VisitedOpen";
		if(sub != null)
			sub.className = "Expander_Item_Sub_VisitedOpen";
		element.style.visibility = "visible";
		element.style.display = "block";
	}
}

function Bd_GetElement(id) {
	return document.getElementById(id);
}