usability – Financial planning site — show a negative balance in italic type?

I have read the discussion from some years ago about whether to use a “minus sign” in front of a negative balance or to put it inside parenthesis. Our website is used primarily by people 45 and older. They may/may not have much experience with investing and financial planning.

Our concern is that displaying a negative balance in parentheses may be unfamiliar to (maybe a significant) percentage of our customers. Putting a “minus sign” in front of it does not seem as visible as we’d like it to be.

We do not want to show it in red type, as we fear (esp. during this COVID-induced financial terror) it is a bit too alarming.

My husband, who is well into “seniorhood” said that he often does not notice a “minus” sign — and suggested putting it in red type. When I said “not a good option” he said just make it much more prominent.

I am wondering if showing a negative balance in italic type might do the trick? I have searched and not seen any examples of this. Would love to research it, but as a first step, going to toss it out here and see what y’all think?