'Idea' has a broader usage and can refer to anything from a simple thought to something more tangible. 'Insight' typically implies something more than a thought, such as information or knowledge of something. 1a. Do you have any idea (knowledge, information, thoughts, guesses) as to what they are planning on building here? 1b. Do you have any insight (knowledge or information) as to what they are planning on building here? 2. I have an idea (a thought, a plan, an invention etc.) that could change the world. 3. He is very insightful (knowledgeable). 4. What are you ideas (thoughts) about it? 5. Can you offer me any insight (information, advice) regarding what I should do?

Good ideia, congrulations on the question.