Hyphen/minus " - " added on Customer Receipt when giving a Discount

Currently when discount is given, the Customer Receipt is not showing the Discount amount in a negative amount. For example, if I'm giving $1 off of $10 item, it should show "- $1.00", currently it shows "$1.00" without the Minus. It causes confusion in customers who think they are being charged instead of receiving a discount. It's a small nuance but we've received several calls already from merchants asking for a fix.