Does Dispel Magic banish Gargoyles or Elementals?

@marcolivier_nIs it correct to say that Disp. Magic should banish Gargoyles or Elementals? If so, how can I know if the spell succeeds or not? only if they are summoned by a spell, and in that case use the standard rules for breaking a spell.

— Mike Mearls (@mikemearls) January 30, 2016