var activeLayer = null;

function showLayer(elementId)
{
	if ((activeLayer == null) || (activeLayer == elementId)) {
		activeLayer = elementId;
		var e = document.getElementById(elementId);
		
		e.style.visibility = 'visible';
		e.style.display = 'block';
		e.style.zIndex = 10;
	}
}


function hideLayer(elementId)
{
	var e = document.getElementById(elementId);

	e.style.visibility = 'hidden';
	e.style.display = 'none';
	e.style.zIndex = 0;
	activeLayer = null;
}

function expandCollapse(elementId, toggleImageId, srcPath) {

	var element = document.getElementById(elementId);
	var image = document.getElementById(toggleImageId);

	if (element.style.display == 'none') {
		image.src = srcPath + 'collapse.gif';			
		element.style.display = 'block';
		image.alt = 'Hide this section';
		image.title = 'Hide this section';		
	} else {
		image.src = srcPath + 'expand.gif';			
		element.style.display = 'none';
		image.alt = 'Show this section';
		image.title = 'Show this section';								
	}
}