Idioms v cliches v euphemisms

What, if any, is the difference between an idiom, a cliche and a euphemism?

What are good examples of each?

I always understood an idiom to be a phrase composed of words that do not literally indicate its meaning, like "put up with" meaning "tolerate". A cliche is phrase so over-used that it almost has no meaning, like "think outside the box". A euphemism is a way of substituting words to soften or otherwise alter the reality or perception of a certain condition. Examples would be saying that someone "expired" or "passed away" instead of having "died" or saying you're "between jobs" instead of just "unemployed".