Expand right floated div to push left div

Question

So, I have a

<div style="width:250px;border: 1px solid;overflow:auto" id="container">
    <div style="float:left;">Vasileostrovsky rayon</div>
    <div id="rightAlignedDiv"> Div which will be expanding </div>
</div>

How can I make the #rightAlignedDiv to expand over the left one. In other words when the #rightAlignedDiv is wide enough, I want it to push the left one to be smaller, and only the left div can move to a new line :).

Here is the fiddle to demonstrate the predicament http://jsfiddle.net/eC9ZX/1/

This has to be solved somehow using css. A JS solution will complicate the logic too much. And it wouldn't be an elegant one.

Answer 1

window.alterWidth = function() {
    var testWidth=parseInt(document.getElementById("testId").style.width);
    var testWidth1=parseInt(document.getElementById("rightDiv").style.width);

     document.getElementById("testId").style.width = (testWidth-33)+'px';
    document.getElementById("rightDiv").style.width = (testWidth1+33)+'px';
    var newImg = $('#com_ibm_ioc_spb_kpi_StatusBox_412').clone();

    $('#rightDiv').append(newImg);


}

Give id to both the div and make overflow auto for first div.

Also try this fiddle http://jsfiddle.net/L774V/