What do the Account Invoice Listing Colors mean?

When you look at a camper's account and you see multiple reservations and general sales invoices with different colors, each color indicates something different. 

First, if the reservation is highlighted green, it means the invoice is paid in full. 

If the reservation is highlighted yellow/orange, it means that there is an outstanding balance on the invoice. It will also have a quick settle button on the right hand side. 

If the reservation is highlighted gray, it means the reservation was cancelled.