Idealism ought to be able to be decomposed into independent factors. First the dissolution of the distinction between the objective and subjective qualities in experiencing. This is what the dream analogy points to in which the apparently independent substance of everything you are experiencing is made out of exactly the same stuff that you are. You might talk of this as being the mind, the same mind constituting the dreamer as the dreamed world; if again it is like being in a theatre and absorbed in a movie, it is both the fact that the theatre, the audience, the screen, the watching and all that makes it up, responses etc., are all just the same mind in its various capacities, and that it is possible to immediately realise that fact without any doubt or speculative shadow - these being two different things, the philosophy one, and the meditative direct experience of its conclusion another. This might be one level of idealism, the ground floor, but there is also the content of the unfolding experience, the source of the movie you are watching, whoever wrote, produced and directed it, or the world-mind as distinct from your mind. The idealism which includes this level as well is a further step, and the direct realisation of it would be yet a further step requiring a different kind of validation.