All solipsism is a form of idealism, idealism need not be solipsist at all.
Solipsism posits that only I exist and that everything else - crucially - other people, are a product of my mind. When I die, everything vanishes: history, politics, art, etc.
Idealism is often presented as a phrase that should be obvious, and one should have strong opinions about it as soon as once hears the word.
Nevertheless, there's are many types of idealisms: some claim that only perceptions exist (Hoffman) , other claims that we can only see appearances, but that a world absent these exists (Kant), yet others posit that we are all part of one mind (Kastrup), or that something remains in the world which is not mental (Schopenhauer). And so on.
It often means that only ideas exist, or that the only thing we can know are ideas (Locke, Hume) or that mental stuff is fundamental, or that the only thing that counts as "real" are those things which trigger our innate dispositions (Descartes, Chomsky).
But idealism is much broader, and arguably richer, than solipsism, which varies mostly (if not exclusively) on intensity: only my life exists, only the past day exists, only the present moment exists, etc.
EDIT: I should mention, the philosophers listed may be argued to belong in other characterizations, this is a unsophisticated form of presenting versions of idealism.