Stands for F****n white kid(s).
Any group of white teenagers or young adults, male or female, who are generally spoiled and rude. They most likely receive a top-notch education, play hockey, and have a pretty awesome phone. This term is used when an aforementioned caucasian does something that any other person of any other race would not do.
Person 1: Look at those white ids at the back of the class.
Person 2: Wow, they're so retarted
Person 1: Bunch of FWKs, eh?