How to resize document in Illustrator?

I have a billboard I made in Illustrator that is the actual size of the billboard, i need to scale the entire thing down to 25% of the actual billboard size(this is smaller billboard then the typical size) Is there an easy way to just scale the whole thing without have to do any adjusting? Almost like you would us Image size in photoshop? The Illustrator file contains all vector images and 1 high res image.