function getWindowHeight() {
	var windowHeight=0;
	if (typeof(window.innerHeight)=='number') {
		windowHeight=window.innerHeight;
	} else if (document.documentElement && document.documentElement.clientHeight) {
		windowHeight = document.documentElement.clientHeight;
	} else if (document.body&&document.body.clientHeight) {
		windowHeight=document.body.clientHeight;
	}
	return windowHeight;
}

function contentIsLargeEnough() {
	var minContentHeight = getWindowHeight() - document.getElementById('header').offsetHeight - 15;
	if (minContentHeight > document.getElementById('content').offsetHeight) {
		document.getElementById('content').style.height = minContentHeight + 'px';
	}
}

if (window.attachEvent) {
	window.attachEvent("onload", contentIsLargeEnough);
	window.attachEvent("onresize", contentIsLargeEnough);
} else if (window.addEventListener) {
	window.addEventListener("load", contentIsLargeEnough, false);
	window.addEventListener("resize", contentIsLargeEnough, false);
}