function __windowOnLoad()
{
	d1 = document.getElementById('id_main_c').offsetHeight;
	d2 = document.getElementById('id_left_c').offsetHeight;
	
	cdmax = Math.max(d1, d2);
	
	if(d1 < cdmax)
	{
		document.getElementById('id_main_c').style.height = cdmax + 'px';
	}
	if(d2 < cdmax)
	{
		document.getElementById('id_left_c').style.height = (cdmax - 300) + 'px';
	}

}

if (window.addEventListener) //DOM method for binding an event
	window.addEventListener("load", __windowOnLoad, false)
else if (window.attachEvent) //IE exclusive method for binding an event
	window.attachEvent("onload", __windowOnLoad)
else if (document.getElementById) //support older modern browsers
	window.onload=__windowOnLoad