The main idea & detailed graphic organizer is a reading strategy for reading. This strategy is a kind of note-taking approach. Like many graphic organizers, it is an organized way to record ideas, thoughts, and concepts. As the below Main Idea Example illustrates, supporting details are reasons, examples, facts, steps, or other evidence that explain the main idea. Major details explain and develop the main idea. Minor details help make the major details clear. Use EdrawMax Online to create a main idea diagram for your classes.