Copyright law exists exactly because it is universally accepted that ideas are not property: Copying an idea or expression of it does not deprive you of your ideas.

The entire notion of "intellectual property" is the creation of an artificial monopoly rooted in very distinct and separate goals from physical property that requires separate laws if you want to restrict copying or exploitation, because property law explicitly does not cover them.

Most copyright laws are also justified implicitly or directly in the legal texts allowing them as creating an incentive for the advancement of the arts and sciences - a temporary monopoly right granted by the state as a deviation from perceived "natural right" - on the belief that granting that right creates more benefits for the public than not having them, by encouraging the creation of more works.

And no copyright law protects your ideas. They protect the specific expression of them. Patents - which do protect ideas - are by design far more restricted and limited exactly because they are far more invasive in depriving the public of use of the very idea for the duration.