<!DOCTYPE html>
<html>
<body>
<div style="background:red;min-height:150px;" id="myDiv">This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text.</div><br>
<button type="button" onclick="myFunction()">Return min height of div</button>
<script>
function myFunction() {
alert(document.getElementById("myDiv").style.minHeight);
}
</script>
</body>
</html>