Replace the minus sign on a number and replace/enclose the negative number in a parentheses
<p>Freemarker Code:</p>

<p>${customrecord_line.amount?string("(,##0.00)")}</p>

<p>Actual result = -1234.56</p>

<p>Expected result = (1234.56)</p>

<p>Note: customrecord_line.amount represents the amount</p>