function blockToggleDisplay(headerId, contentId){
	var revHeader = document.getElementById(headerId);
	var revContent = document.getElementById(contentId);

	if (revContent.style.display == 'none')
	{
		revContent.style.display = 'block';
		revHeader.className = 'instructionBlockHeaderExpanded';
	}
	else
	{
		revContent.style.display = 'none';
		revHeader.className = 'instructionBlockHeaderCollapsed';
	}
}