Leaving a job is always a little bit awkward, no matter how good the terms you’re leaving on. It’s just a little bit… awks. If they like you and appreciate your work, they probably don’t want you to go and wonder why you’re leaving. If they don’t like you and force you to go (aka fire you), then your feelings are bound to be a little bit hurt. So in either scenario, you’re probably feeling a little weird. The least your employer can do is help make it as painless as possible. There are a few ways to do this. They should keep things polite and cordial, no matter what. They should try to help you smooth your transition as much as they can. And they should refrain from asking too many questions. 

Sure, they might like some feedback on the company/their management style, but they’re not entitled to know what you’re doing next. You might elect to tell them if you think there’s goodwill, but you just as well might keep that info under lock and key, lest something nefarious happens.